Al's 6x47L

[J. Pendergraft]

Sizing down

Al,
You are correct, the case needs to be fully supported to size down the necks concentric. What about using a die base similar to the bases used with neck bushings then have a second piece that can be pressed down from the top to size the neck down. This could be made fairly easily I think. I'm thinking you would use an arbor press to do this sizing operation.

You are not using the shotgun powder with a bullet are you?

 

[alinwa]

Lynn,


The ONLY way that I know to approach the primer pocket problem is to keep loads lower than the "primer pocket expansion pressure" of your chosen brass.

That's it. The primer pocket is my ceiling.

Now, as for fixing it. IME you can't "fix it"....... I've tried every primer pocket swaging tool I've ever heard of. They don't help for me. I've thrown them all away or use them for rod stock or paperweights or nosepickers or whatever.

BUT..... in light stuff the Lapua brass coupled with small primer pocket and flashhole demonstrably takes more than usual pressure... THIS POST is about the 6X47L. PRIOR to this case my small case of choice was the 6BR as you well know. I'm shooting right now alongside my bro-in-law's .243AI and I'm easily running 300fps faster than him with limitless case life. He's eternally fighting the primer pockets. The solution is simply to change chamberings which he will soon do.

Currently there are 3 high pressure cases available. .220R, 6BR and 6.5X47L. That's IT! There is nothing comparable in the 30cal class......Now I'm trying the 300WSM because IMO the Win brass is tough and the enlarged casehead leaves more meat for resisting expansion. Will it work??? I DON'T KNOW I'm trying it. Think back on this..... you've watched me take 7 YEARS to choose a 30 caliber case! I spent a year of that pursuing the BooBoo case and until Tooley told me "probably the easiest way is to pick up a bunch of cases on a trip to Europe" it just didn't sink in! I'd pay dearly for a thousand UNDRILLED Lapua cases in say 300RUM case size.


I STOP when primer pockets are going south. And NO, you can't stop them or contain them although IMO "seasoning" them helps to harden them quite a bit. A ten times fired case will take more pressure than a fresh one.

I mean it when I say "I Think A Case Is Just Getting Good In 5 Firings"........


And please all...... understand I AIN'T SELLIN' NUTTIN' HERE!!! Just sharing my views. I make absolutely NO assertions about being "right" about any of this. This is just what works for me. Or what I'm trying right now.


I'm a tinkerer. But I tell you this.... I've got a boatload of CRAP that I've paid good money for over the years THAT DOESN'T WORK. A drawer full of "custom dies" that don't work f'rinstance!

anyway....


al

 

[alinwa]

Ok, I've got some time so I'm going to try and step-by-step my brass-making program with this cartridge.

Jim asked for it


I may run out of time and have to do this in multiple posts ALA Gene Beggs

I'm not going to number these points because some of them may be out of order. Each paragraph is a separate step.

I'm addressing Jim in particular but I'll try to use terminology which can be understood by beginners too.


This list pertains only to the conversion of the 6.5X47 Lapua case to something I'm calling the 6X47L.

____________________________________________________________

I do NOT sort my cases, just grab up the whole box of brass and load a tray of say 100.

Now I take the time to visually inspect everything under light.

I neck down using a Redding one-piece 6BR FL die WITH the expander ball. I use a polished long-taper "ball", more of a mandrel. (I'm looking for a better way to do this step... pic below of sectioned case shows WHY look closely at the eccentricity generated. ) Anyway, this is THE important step. I iron out the neck perty good by necking it down and then dragging the ball back through it. Included in this step is setting my crush-fit. Through trail and error I set my die JUST so.....Such that running the case into the 6BR die bumps back the shoulder so that EVERY CASE IS IDENTICAL as far as headspace and EVERY CASE IS IDENTICAL as far as crush fit. And this is why I short-chamber. At this point either you've got to understand just how much pre-figgering goes into this or I've got to spend some time explaining just HOW to make it so that you can do all this. My chamber is so short that I can re-set every case to my specified "crush-factor" just like a PPC...... When the case comes out of this step the headspace is set identically on all of the cases and it's set to TIGHTLY fit the chamber. For a 6X47 that is chambered too long you CAN use the stepped shoulder but it' a crookedy thing! I like to get into the shoulder meat, I prefer it.

___ A CAUTION___

Make absolutely sure that your reamer is ground such that when all is said and done your case fits TIGHTLY at the shoulder and has minimal "gapspace," the clearance at the end of the neck.

IF you push the shoulder back and IF your neck is too long on the case YOU WILL CRIMP ONTO YOUR BULLETS!

BAD juju.....

AT THIS POINT you must somehow KNOW where the end of your neck is. I find this point by using a Sinclair Chamber Length Tool or by cutting a neck back and making a mandrel for it OR I'll cut a caseneck off, take out a section, insert a long FB bullet BACKWARDS and use this to actually MEASURE where my neck ends. I can post pix if need be....... This is important.

Now since this is a brand NEW and for me experimental case I took this whole thing to extreme. I had my first 6X47L chambered using a 6BR reamer. This results in a neck which had 50 thousandths of gapspace..... NO CHANCE of crimping on the bullet. This was (is) my "Test Mule" (Although it's shooting perty steenking good!) NOW I have had my SECOND barrel made up which is exactly .002 FATTER in the chamber. The first reamer now is my resizing die reamer AND still a great 6BR reamer. My "best" after 6 tries. I now have a monstrous fine fireforming chamber which is EXTRA LONG IN THE NECK so that I can fireform cases, hammer out the necks and THEN turn them to fit my Match chambers. (pic below shows how the 6BR compares and why this can work) ..... but I digress.

___________________________________________________


And......


___ An explanation of "crush fit"____

"Crush fit" for fireforming means that the cases must be LESS THAN ZERO headspace clearance. This aint ABOUT SAAMI Spec GO Gauges. I chamber to an undersized go-gauge. A good crush fit means that you will have to "heel" the bolt closed, nearly bruising your palm. GREASE YOUR LUGS.

In My Opinion a system must be set up wherein one can MAKE the cases to be a crush fit in your chamber. No slop.

____ Back to the program_____


I now have a case which is necked down and ironed out fairly good in the neck and is most likely TOO LONG in the neck!


I ream the inside of the neck with a Wilson reamer. I drive the case using a Lee iris style caseholder mounted in a small tabletop drillpress laid down (pic below)

I run a tightly wound plug of steel wool inside and try to polish it out a little. This step also clears out little chips and such from the reaming. To make this tool I wrap 0000 steel wool around a .22cal brass cleaning brush.

IF the insides clean up to my satisfaction (mine did) I'm now ready to neck turn. IN MY CASE the stock diameter Wilson inside neck reamer produces a fine fit on my Time Precision neckturning mandrel so's I can proceed posthaste.

I neck turn.

I trim to length.

I inside/outside deburr.

I run a K&M long taper reaming tool in to JUST KISS the inside and remove the face burrs.

I again do a polish with the steel wool tools. (pic below)


In the end I come up with a trimmed up case which:

-Fits TIGHTLY into the chamber lengthwise, crush-fit with no endplay at all.
-Fits closely for overall length, small gapspace.
-Is ready to fireform. Incidentally, these cases SHOOT extremely well during fireforming. I'd fireform at a local match if it's at all windy. If it's a trigger pull I'm gonna' try everything possible to go for small group! Screw fireforming.....



______________________________________________________________

Now it's time to fireform.

With this case I've settled on H4350 for 105/107/108/115gr bullets and I currently feel that this powder is "fast" enough for good fireforming. I don't feel the same way about 4831 or RL19 for instance, but that's just me... If my cases weren't popping out sharply I'd waste a bullet and some barrel and fireform with a 68gr bullet and some faster powder.

But H4350 yields straight, consistent cases so far. ZERO measurable runout after 2-3 firings. All cases feel/resize/seat THE SAME except for a few. This is my first cull, actually more of a "grouping" or "sorting" than a cull......

NOW I can also finally sort by weight etc if I so choose. A perfectionist "weight sorter" would now boil out the cases and weigh them on a bell curve. I don't do this.

My second "cull" also isn't a cull. I sort when resizing by visually identifying the perfectly symmetrical, the slightly offset and the "scrubbed" cases shown earlier. So far I can't see a difference on the target but hey, ya' gots to have SOME method of picking out the "best" cases.


Now after about three firings I get a little weird....... I start paying special attention to seating pressure and I visually re-inspect all of my necks. Sometimes I find one which had a grain of powder lodged in it, or a hunk of steel wool or a chipof brass or a small animal..... maybe a nick. I set out cases which seat a little hard and just touch them up with steel wool a little.... generally I can get most of my initial batch to come into spec, "Perfect Cases."


After 4-5 firings the whole herd just generally comes into line. I might set out a few for "something" but this batch of 6.5X47 Lapua cases has yielded a near perfect batch of cases so far. ONE split shoulder from the factory and that's it. I've got 148 out of 150 usable cases (I wrecked on setting up my neck turner ) "Sorted", but all usable.




OK, I'm sure I've missed a few things or been unclear. Might have even SKIPPED a step! But I'm going to post this just to clear my head.......


Sorry Jim to wait so long to actually sort this out but it's a lot of typing and thinking......

Thanks for waiting


al

 

[alinwa]

Al:

As I understand it, you trim your brass significantly prior to fire forming. Since the 6x47L does not have a very long neck (compared to the 6mm Swiss Match for example) why would you not wait until AFTER you have fire formed in the dedicated FF barrel?

It seems that your could "square" the brass during FF and then make a square trim that leaves you with a longer neck and just a little gap in front of the case mouth. What say you?

Jim

Jim,

hopefully the prior post answers your question. YES I'm a big believer in fireforming prior to final turning the necks. My 3 closely related 6BR reamers ALSO all have different necks I've got .271, .268 and .266 necks and YES I DO actually make my brass all smooth and shiny before my final Match Fitting cuts but this requires beaucoup bux or time spent. In the post above I've tried to explain how a "normal person" can make good brass with only one barrel!


I just got my second barrel in, Shadetree tuner on it too....... now my entire lot of cases that I've been shooting in matches with my first barrel will get RE-turned and trimmed to final scrupulous fit and they'll be my NEW match cases! (with 4 firings already in them!)


All jazzed up and ready to go....... Thurs-Fri-Sat final-trim those cases and SHOOT all day every day! Can't wait to go to bed just so's I can get up to shoot......


LOL


al

 

[alinwa]

Al,
You are correct, the case needs to be fully supported to size down the necks concentric. What about using a die base similar to the bases used with neck bushings then have a second piece that can be pressed down from the top to size the neck down. This could be made fairly easily I think. I'm thinking you would use an arbor press to do this sizing operation.

You are not using the shotgun powder with a bullet are you?

Joel,


I've got a guy who's offered to work on that idea. I hope to buy one of his units if he does. Otherwise I'm probably going to either build a top for one of my Neil Jones dies or try a workabout using the Redding sliding bushing concept.

I wouldn't use an arbor press as getting the thing back off the neck would be a bear and plus I use a tapered expander mandrel to bring the neck back out to usable and iron it again.


The sequence of cases that you see pictured show the number of kliks of Win Superlite I used on a Harrell, no bullet. This is VERY safe. Read Ken Howell "Designing & Forming Custom Cartridges: For Rifles & Handguns" for a rundown on the technique. In short I started with a half case of SHOTGUN powder, walk outside, point at the sky and Poooff.... now work up to BOOM! and perfect cases. I've used pistol powder, COW, undersized bullets etc and this is my favorite and completely SAFE way.


WEAR EAR PLUGS!!




al

 

[alinwa]

I've got an idea for the necking down process.

If I have Neil Jones make me the sizer he can also make me a stepped bushing which goes from 6.5MM down to 6MM. Of course the actual numbers will be more like .286 stepped down to .265 but I THINK this may work to capture the neck during the downsizing stroke......

I'll finish the stroke with another bushing.

Comments?

al

 

[alinwa]

Here's a picture of the tool that I use to find the actual end of my neck. I remove a hunk of the neck, insert a bullet backwards and use the leftover ring of neck to fir out the end of the bullet.

Also a couple pix to show just how skanky-crooked these things are necking down. I'm going to stop until I find a better way.......

al

 

[Law Dawg]

The process

Al:

I am "feeling" your process. I see the light . . . most of it. Questions:

1. Which fire form process are "into" with the 6x47L -- shotgun powder and no bullet or light bullet and H4350?

2. On the shotgun fire forming, are you just finding the correct charge to give you the fire form fit you want by poping the primer on the charge with no filler of any kind?

3. I read your process as fire forming on the crush fit which completely nuls any need to fire form on the conventional thinking "hard jam" which I don't believe works at all -- impossible in my experience. What say you?

4. Why are you shooting a .266 chamber neck on the 6x47L, and what is your loaded round neck clearance?

5. I can see that your fire forming process helps you sort brass at a glance by exposing the internal flaws as viewed from the outside of the fire formed case. The first thing I though of was "this is Al's version of an in your face Junke machinne reading of what you otherwise can't see." Again, what say you?

Soaking it up,
Jim

 

[alinwa]

Al:

I am "feeling" your process. I see the light . . . most of it. Questions:

1. Which fire form process are "into" with the 6x47L -- shotgun powder and no bullet or light bullet and H4350?

2. On the shotgun fire forming, are you just finding the correct charge to give you the fire form fit you want by poping the primer on the charge with no filler of any kind?

3. I read your process as fire forming on the crush fit which completely nuls any need to fire form on the conventional thinking "hard jam" which I don't believe works at all -- impossible in my experience. What say you?

4. Why are you shooting a .266 chamber neck on the 6x47L, and what is your loaded round neck clearance?

Soaking it up,
Jim

1. For the 6X47L I have found H4350 and a full-sized (105-115) bullet to be suitable. This is abnormal IME, on large cases I normally have to fireform using a light (68-70) bullet and fast powder. For instance, I spent 6 yrs playing with various blends of the .243AI and for this cartridge it was imperative IMO that the initial FF load be HOT and FAST with a LIGHT bullet. The combination of H4350 and the 6X47L case works as-is, no need to go the fast powder route.

The shotgun powder stuff was a digression, I only use this method to blow necks OUT...... those were 30X47L rounds.

2. Correct, no filler. I start with 1/2 casefull, point at the sky and fire. Work up to achieve desired result. Once a load has been established and if going outside is a pain (raining?) then you can load the round, insert a TINY piece of toilet paper to hold the powder in and lay the gun down and fire out the window or whatever. IF YOU USE PAPER IN A WAD, you must back down the charge. The "tiny piece" of wadding that I use cannot be thrown 3ft.....if you roll up say a pea-sized wad, something that you could throw to the wastebasket, then I say BACK OFF the powder charge and work back up...... just a half-inch by half-inch square of toilet paper though, doesn't build significant back-pressure. TINY and LIGHT are the watchword....... not a plug of paper.

This info is of no use for the 6X47L, I apologize if it's confusing.

3. ABSOLUTELY CORRECT!!! And of all the garble in my looong description this is THE ONE THING that needs to be taken to heart. Neck preparation techniques vary. For instance I choose to cut (ream) the snarf off of the inside of the neck and check for donuts..... this may not be any advantage at all but I do it. I treat my casenecks like my crown. Don't TOUCH my crown and don't TOUCH my casenecks! I want EVERY CASE to feel exactly the same while sizing/seating. The ONLY way I know to accomplish this with regularity is to crush-fit the cases.

"Seating the bullet long" is completely useless. WORSE than useless because it actually makes the problem worse than if you just let the case slam forward on it's own. The bullet WILL NOT under any circumstances hold back the case.......... Easy to test and establish as fact for any and all who care to test it.

4. I use the .266 nk only because I can't go any thicker and still have a fireform barrel! My fireform barrel is a .268nk which is as thick as I can go and still ream. IMO thin .262 necks are an anachronism, a relic of another time and unnecessarily fragile. Also, I want as thick a neck as possible because with the slower powders I feel that sometimes it really helps consistency (ES) to keep bullet pull HIGH as possible but still consistent. PPC shooters are spoiled With a PPC you really can just drop a charge of 322 (I know, I know but it still friggin' SHOOTS at 70-80 degrees!) into a case, drop a bullet on top of it, ease the round into the chamber and shoot bugholes....... the 30X47L is equally forgiving...... but the 6X47 IS NOT! It ain't as finicky as traditional overbore rounds like 6X285 and such but it ain't automatic like the light bullet stuff.

Heavy neck tension allows me to cover a wider temp swing too. I went to my first 600yd match and asked "where do we load?" and the guy looked at me like I was drunk! So we preload. Always. And mornings are cool and afternoons may be hot. And I may load in WA and shoot in CA.....and so on and so on. WE DON'T HAVE THE OPTION of adjusting loads! It's just part of the game. A good stiff neck tension helps to hold back the bullet when I'm jumping. IN MY OPINION, this help ES by making the initial "startup burn" more consistent through temp range. In a way it's just like the factorys crimping many of their loads for the same reason.


As far as clearance....... here I'm going to draw the wrath of many. With boattails I use from .002 total clearance down to "scuff fit"....... maybe a tenth? Just for safety reasons I never use the "scuff fit" if I'm jamming the bullet deeply. I load such that I can FLICK the bolt open and closed as I currently SUUUCK at trying to read conditions over 600yds. My current style includes machine-gunning... although in the last match I had two groups take over 7 minutes with the last one being 9min 47sec in Heavy. Made my head hurt. My point is, when running really close tolerances I feel better if I can FEEL if something's in there. My cases won't close easily on ANYTHING, like a thread from a cleaning patch causes bolt refusal....

________________________________________

Safety Caveat-------

For everyone reading this, please DO NOT follow this advice unless you KNOW your clearances!!! If you don't KNOW how to use the tool to find the end of your neck, DON'T RUN TIGHT.

If your cases "grow" and require periodic trimming DON'T ATTEMPT THESE TOLERANCES!!!

If your sizing die isn't specifically fitted to your chamber DON'T TRY THIS STUFF!!!

please....

__________________________________________

With FB bullets I expect to use from .002 to .003 and from what I hear I might have to try .004........ But I've never really explored this yet. My work had all been with making VLD's shoot.




OPINION ALERT!


(I know, this whole post is OPINION, but this one will offend people... I know this from experience.)


I believe that the neck is VITALLY important, second only to "crush-fit fireforming." And on the subject of clearances we must not apply point-blank FB bullet logic to the thing. WITH A PPC or a 30BR shooting FB bullets you CAN open your necks up to even .005 clearance and the bullet will "self-straighten" and fly 100-200yds into a bughole.

With VLD's and honking boattails I don't believe this to be true.

With PPC type stuff the bullet is not only flat based, it's IN THE NECK with the powder charge being directed straight against it's base and pushing it forward.


Now hang a big old tapered boattail on it..... NOW the firestorm of swirling gas is BUFFETING the base of the bullet sideways, AND the bullet is longer with a shorter bearing surface to begin with.....


NOW hang that boattail right down into the powder chamber proper and REALLY let the firestorm at it!


See where I'm going with this? The neck clearance is the critical BUSHING which maintains alignment as the bullet gets pounded into the lands with 600 POUNDS of force..... It ain't an easy entry this..... We talk about "chamber pressure" and "copper units of pressure" and psi and such and it's kinda' foggy but picture this, it would take a 450-600lb block of concrete setting on the ram to start that bullet! The ONLY thing keeping it straight is the bushing effect of the fitted neck.


But I digress.....A'gain.

I'll drop all this speculative "why it works" stuff and try to regroup....


WHEWwwwwwww


LOL


al

 

[alinwa]

Al
When your done with all of this prep are you neck sizing,full length sizing or just knocking out the primer and letting the bullet seat to the click?
Lynn

Lynn,

I full length size every time, EVERY time.

Yes I can often just knock out the primers, seat bullets and move forward without doing anything and I often do that when I'm out squirrel hunting or something but for competition rounds I'm all about EVERY SHOT THE SAME..... in fact the idea of running the case through a bump die or a body die or something "every 4-5 rds" is repellent to me....

"EVERY SHOT IDENTICAL" is my idea.

With most of my VLD bullets there's no click. I've shot many PPC's/BR's this way though...... down around 3250. Again w/H322.

al

 

[Law Dawg]

Neck tension

Al:

In the long range prone game, MANY if not MOST of the shooters are soft seating, although the International Palma Rules discourage this. The soft seat is a reaction to so many rounds being fired with the hopes of not having to chase the lands. However, I have seen many a bullet left in the barrel and the powder in the chamber during a cease fire.

I have always used a heavier neck tension as I found out long ago that I could get a lower and more consistant ES with higher neck tension. I also like the thicker necks. I am with you.

I will digest the rest after I eat me a good steak.

Jim

 

[michaelb]

Al,

You mentioned the cases had a "scrubbed" or "frosted" appearance due to the die not being hardened.

1. Why would die hardness cause this condition?
2. How would one harden the inner surface of a die without suffering distortion to the important thread fit on the die body?

Thanks, Mike

 

[alinwa]

Al,

You mentioned the cases had a "scrubbed" or "frosted" appearance due to the die not being hardened.

1. Why would die hardness cause this condition?
2. How would one harden the inner surface of a die without suffering distortion to the important thread fit on the die body?

Thanks, Mike

Mike, that's a fair question. It seems completely reasonable to assume that the brass SHOULD NOT EVEN CONTACT THE DIE provided you use lube. This is how a car motor doesn't wear out........ But in reality and in use THIS IS what cases sized in an unhardened die look like. I use lots of hardened dies and they polish the cases up shinier. I've got no pix because I'm not currently shooting anything which has a finalized set of dies but if it gets important enough I'll fire up a PPC and size some cases.

GOOD, polished and hardened dies are a PAIN to procure....... In fact this rifle I'm writing about won't have a hardened die until end of April PROVIDED Neil J gets back from Fla on time! Jim opted not to make dies for it....I was going to use a Harrell die but then decided I needed Jones' expertise to make a hardened sizer AND FORM DIE..... Jones Neck bushings are unique in the world. Quite a story here....... We'll see how it plays out.

The dies are hardened in a vacuum furnace. There have been as many as three "acceptable" heat-treating places in the US since I've had dies made. Fireball in Mass is one I remember, there's one in TX that folks are using a lot now..... problem is you need to make up "runs" of dies to make it pay. Another problem is that if the batch warps or is otherwise screwed up it becomes a can of worms. It once took Jim Borden 3 tries to get me a proper resizer made for a barrel. He had to re-make the dies three times because they got screwed up in heat-treat. He didn't charge me. This is no way to make money.

These are some of the reasons that I called Neil today and have decoded to wait 3mo for a proper die. I'm stuck with my old barrel for now... I did shoot the new Krieger today, got a taste..... DOTS!!!! It shot 6 groups in a row BETTER than my old barrel has...... and I haven't even TURNED the tuner yet!


And I can't get a die for it, and matches are coming up.


bummerdealdude.... life marches on.


al

 

[alinwa]

Some initial findings from load workup today:

My first 6X47L barrel is a button-rifled 28" Shilen ordered from Brownell's stock a few years back just to fill an order. It shoots OK. It's my "workup barrel" and it has an excessively long neck portion, zero freebore and a chamber which measures .007 larger diameter than the virgin cases. This is the barrel I've shot in the last two matches. It ain't "crisp" IMO but it's heck on spotter discs!

Today I fired the new cut-rifled 29" Krieger, mainly to get some cases to send off to a die maker. I don't have a single die (of seven!) which is FAT enough to accept this case so I just punched out the primers with a Wilson pin and dropped the bullets in on the powder charge with my fingers. I worked up from 3000fps to 3225fps, took six firings before the brass tightened up. This chamber measures .009 over the virgin case. The gun went from vertical to vertical about a bullet hole through the workup, flat dots at 3150fps.

I'm shooting an older lot of Euber 108's because I've still got about 3500 of them. I trust them and they're a great bullet for me to experiment with. I shoot my Shilen barrel at 3150fps. This takes 40.04gr of H4350.

To get the Krieger up to 3150 took 2 whole grains more powder. At 42gr it hit 3150, single digit deviation. At 43gr it clocked the 3225 with more dev and 1/4" vert. I stopped at 43gr because the case was so full that I could just barely get the bolt closed. I just jiggled and tapped to settle the powder though, a long, wired drop tube should allow me to go another grain in this big case.

Primer pockets never loosened a drop.

I'm curious whether the two extra grains are from the .002 larger chamber?? Or the cut-rifled Krieger?? or just luck of the draw. Time will tell.

The Shilen is an 8-groove, the Krieger a 4-groove.

It was hard to unscrew the barrel, it's showing great promise.


I will post some pix soon of the hammered out brass... it's TIGHT, like stretching the chamber tight. It measures .477+ above the web!!! I don't think that the bulge looks excessive, really. These 5 cases sprung out concentric and the web has stretched probably .003+..... so the "step" in the case is only a thou or two.... SuWHEEEET!


al

 

[J. Pendergraft]

Al,

Is the new barrel .236 or .237 bore diameter? What primer are you using?

Thanks,
Joel

 

[alinwa]

Al,

Is the new barrel .236 or .237 bore diameter? What primer are you using?

Thanks,
Joel

Joel, good question...

I don't know the bore diameter, I just called Bruno's and had him send the barrel out to Borden's..... it's what Lester had in stock in 8" twist. I'll see if Jim kept the paperwork or if Lester knows. This is still "in development" in my mind so I just missed this point.

Primers are Fed 205M's.

al

 

[a.JR]

Hi Al, I follow your developments with interest as it goes to areas i have never ventured to .. Will you keep us informed as to how this transfers to the competition targets as you go ??..JR..Jeff Rogers

 

[J. Pendergraft]

Joel, good question...

I don't know the bore diameter, I just called Bruno's and had him send the barrel out to Borden's..... it's what Lester had in stock in 8" twist. I'll see if Jim kept the paperwork or if Lester knows. This is still "in development" in my mind so I just missed this point.

Primers are Fed 205M's.

al

Al,
You probably know why I asked. I was thinking maybe the Kreiger is a .237 and your Shilen was a .236 thus the reason for needing more kick to make the same velocity. Lots of folks have gone to .237 thinking they are easier on the bullets in the higher velocity chamberings.

 

[alinwa]

Three pix from slightly different angles in an attempt to show the .009 swelling........

These cases are from the newest chamber, REALLY swelled out fat. The virgin brass started out at .4684 and these cases measure .477+ so they're swelled out almost .009. I fired these cases 8 times to tighten them up sufficiently for the die maker.


I talked with Neil and I think we'll go with a tapered sizer on this one. I'm considering using .0015 sizing effect @ the shoulder and .0025 @ the base.

They shot well.


Jeff,

Yes, although I'm currently only shooting local matches. So far the "test" barrel has done OK.

Joel,

Yup, gottit.


al

 

[Charles E]

Got my NBRSA News Friday. Buried in the financial report was the statement that for 2008, NBRSA had 1,632 members. Assume a similar number for IBS membership. Note that most NBRSA and IBS members don't shoot 600 & 1,000 yards; they're point-blankers.

Given the number of "views" for this thread, I'd bet A LOT of people viewing aren't benchrest shooters. "Benchrest" sorts make certain assumptions about the strength of components, actions, etc. And certain assumptions about measuring, and the tools used to measure.

What Al is saying is interesting. I don't say it is unsafe. But as with anything borrowed from Benchrest, which tends to use pressures well beyond SAAMI, there could be conditions under which it is unsafe.

So enjoy, but be careful.

FWIW