Tight Bolt Revisited

[chino69]

Max. loads

Your shooting max loads in new brass tells me you've not been shooting a 6BR for very long.
I also would never advise anybody to shoot book max loads in a Ackley Chambering without first working up to that point with sacrificial cases.I see this in print all of the time and on cases like the 22-250 or 223 it probaly doesn't matter.
On a case like the 300 Weatherby it matters a whole lot.
Lynn

Lynn,
What I was saying with respect to fireforming for the first time in an Ackley chamber is starting with the max. load for the parent cartridge. The max. load for the parent cartridge is enough to blow the shoulder out with sharp edges properly. I've found that anything shy of a 'snappy load' will yield rounded shoulders which require two or three subsequent firings to achieve a properly fireformed case. I've been shooting Ackley chambers for about ten years now; three different barrels in .22-250 AI, three different barrels in .243 AI, two different barrels in .250 Savage AI. I've worn several barrels out, have my own reamers, custom dies, etc. My Ackley chambers all have a .004 crush fit on virgin parent cartridge brass. I know a little of what I speak.

With respect to the 6mm BR, the first of which I acquired five years ago, came with recommended loads from the former owner. This was a Remington 40X sporting a Hart 1:14" smithed by Clarence Hammonds. A buddy of mine just had a 1:14" 6mm BR put together by Bruce Baer. We traded notes and loads back and forth; he loads hotter than I do. For example, we both shoot 65 grn. Hornady V-Maxes in our rigs very accurately. His load is 35 grns. of Varget with CCI 450 mag primers; a little warm, yes. When he gave me his load, I began around 33.5 grns. as my start point. My load ended up being 34.5 grn. of Varget. I also have a Kreiger 1:7.5" barrel that I had put together to shoot the 105s and heavier. A friend of mine has a Kreiger 1:9" that he had put together with the same reamer that chambered mine as well as Twuds by Clarence Hammonds. My buddy with the 1:9" gave me his pet load shooting 95grn. Berger VLDs. I started, as in the above example with the 1:14", shy of his max. load until I found my 'tune' for that bullet. My development for the 105s started at the mid point of the reloading tables and I found my 'tune' between mid point and max. I've been shooting the 6mm BR for six years.

If I'm missing something in my approach to reloading please fill me in but I'm pretty certain my methodology is safe and right. I'm not being a smart ass just a little more clarity on your above post. I don't claim to know it all and if I'm wrong or doing something outside accepted safe practices, I'd like to know.

Regards,
Lou Baccino

 

[Lynn]

Chino69

Lou
It is 5:20 AM in the morning and I'm headed to work.I will post you back when I get home.
Lynn

 

[chino69]

Twud sticky bolt issue part ll

Twud,
After talking the other night I went to my files and here are my loads for my 6mm BR 1:14" Hart. Needless to say, these loads are safe in my rifle and I indemnify myself from any statement or claim they will be safe in yours. I only post this to help you analyze and solve your problem by giving you another data point for comparison.

DO NOT ATTEMPT THESE LOADS IN YOUR RIFLE WITHOUT SAFELY WORKING UP TO THEM! BEGIN AT LEAST 10% BELOW MY LOADS FOR SAFETY.

I know I don't need to tell you that, Mark, but the above statement was for litigious vultures that may visit this site and be in need of business.

65 grn. Berger with 31.0 grn. VV N135 with Federal small rifle primer. Velocity = approx. 3400 ft/s. A one hole load, no problem.

65 grn. Hornady V-Max with 34.5 grn. Varget CCI 450 mag. primer. Velocity = 3450 ft/s. A one hole load, no problem.

68 grn. bullets (Hammonds, Starke, Fowler) with 33.4 grn. Varget CCI 450 mag. primer. Velocity = unknown

70 grn. Nosler Ballistic Tip with 33.0 grn. Varget CCI 450 mag. primer. Velocity = 3250 ft/s.

All of the above shoot extremely well in my rifle and hope this helps.

Lou Baccino

 

[henrya]

I think Boyd is right about this being a brass/chamber fit matter.

If the "well known benchrest gunsmith" who chambered this rifle was consulted he could likely say for sure. Call him and ask about sending him some of your brass so he can measure it. He'll need to know there's a problem so he can correct yours and any subsequent rifles he might build. He might need to buy a bigger reamer for the current lots of brass like yours.

If you know the particular brand of die you're using isn't made to correct specs then change dies. Getting a Harrel would be one solution. But first establish why this is happening. Work with your gunsmith to be sure where the problem is. If he won't help, change gunsmiths.

 

[Twud]

Fire Forming

Gonna" try and hit the range Wednesday. Need to reload some cases for this purpose.

 

[chino69]

Different brass lot

I think Boyd is right about this being a brass/chamber fit matter.

If the "well known benchrest gunsmith" who chambered this rifle was consulted he could likely say for sure. Call him and ask about sending him some of your brass so he can measure it. He'll need to know there's a problem so he can correct yours and any subsequent rifles he might build. He might need to buy a bigger reamer for the current lots of brass like yours.

If you know the particular brand of die you're using isn't made to correct specs then change dies. Getting a Harrel would be one solution. But first establish why this is happening. Work with your gunsmith to be sure where the problem is. If he won't help, change gunsmiths.

You might be onto something with the different lot of brass issue. I have a chamber reamed with the exact same reamer and have had no problems with my 6mm BR. I bought that lot of brass approx. two years ago. I happen to have a friend who works in this smith's shop and informed me it took awhile to get his reamer. It's just possible that the reamer was spec'd. on the then current lot of Lapua brass, which may have been more than a year ago. If the current lot of Lapua brass has changed dimensionally, i.e. larger at the base, as some have reported, that would certainly fit this scenario.

Lou Baccino

 

[chino69]

Tight chamber in back

Try this. Put a bullet in the neck of a piece of fired brass and chuck the neck of the case in a cordless drill that is set to low RPM range. (The bullet is to keep the neck from collapsing.) Lay the drill on its side with the back of the case supported. I used the side of an open wooden drawer. (at right angle to case) Use a coarse diamond lap or some wet and dry wrapped around something flat, held parallel to the CL of the case. Spin the case and take no more than .002 off of the diameter at the front of the extractor groove, holding the abrasive parallel to the case CL. Polish with 0000. Now refire the case with the same load that caused the problem (assuming that there were no other pressure signs) If the problem persists, I don't know what is causing it, if it does not, your chamber is a bit small in the back. This can be remedied with a different reamer that is larger in the back, or polishing out the back of the chamber. Either operation will require a lathe and an experienced operator.

Agree with all the above. Another fix is send a Redding small base body die to Jim Carstensen (JLC Precision) and problem will be solved. He'll need 5 or 6 fireformed cases.

Lou Baccino

 

[chino69]

Guess?

Boyd,
The round is fired. The brass expands to fit the limits of the chamber and then springs back, more so in the body than in the base. The bolt handle is hard to raise, but does raise. Bolt is drawn back with no resistance and round is ejected. You chamber the same pc. of brass it goes in without a hitch, the bolt closes without a problem and opens back up without a problem.
What changed? Shouldn't the bolt be just as hard on the second chambering?
I'm not arguing your point, I just don't understand mine.
Mark

Mark,
Just a guess on my part. When you chamber the same piece of brass the second time, you could actually be re-sizing the base a 'sqootch' using the mechanical leverage of the bolt and the tightness of your chamber. This would explain why the bolt will now open easily. It only takes a little interference on a tight chamber to cause this. Consider also that some are saying Lapua brass has changed ever so slightly dimensionally. A simple .001 or less on a match grade chamber is going to screw you up. Just more things to consider.

When you finally unravel this problem and get it resolved, you will have either increased your future trouble shooting skills or seek solace in the warm embrace of strong drink and the siren song coming from women of ill repute. It takes a good man with intestinal fortitude to dissuade the women of ill repute and not fall victim to their sweet song of defeat. I can't help it Mark, I wax poetic from time to time.

Keep us posted because this is one of those interesting problems whose final resolution will be of interest.

Lou Baccino

 

[Twud]

Bruce Thom

Got a reply from Bruce Thom today. He feels it's a chamber problem and want me to send him the gun. Don't think we're to that point yet. Gonna' see CH on Thursday. He wants to shoot the gun in his back yard. I think he thinks I'm over reacting.
aboz

 

[chino69]

Chamber problem

Got a reply from Bruce Thom today. He feels it's a chamber problem and want me to send him the gun. Don't think we're to that point yet. Gonna' see CH on Thursday. He wants to shoot the gun in his back yard. I think he thinks I'm over reacting.
aboz

Mark,
A thought just occurred to me that would be real easy for you to do. Clean your chamber thoroughly with alcohol or brake cleaner; make sure it's absolutely clean of any residual oil, etc. Do the same to new brass that you have not fireformed yet. Load up some rounds and shoot and see what happens. If your chamber walls are too slick, the case is sliding back upon firing and in doing so jamming your bolt locking lugs tight due to excess bolt thrust that is normally countered or negated by the case wall sticking on the chamber wall. This would explain your bolt opening hard but yet opening easily when you re-insert the freshly fired case. Your chamber walls may need to be 'scuffed' or roughed up a bit to enable the resultant forces of recoil to be absorbed by the chamber walls. If your chamber is too slick, the recoil force is directly rearward; jamming your locking lugs. Keep the lube on the back of your locking lugs. If this works, have our buddy scuff your chamber walls a little, start shooting and get ready to pop some groundhogs this spring and summer. Keep us up to speed.

Lou Baccino

 

[Lynn]

Twud

Twud
What Bruce is saying is your chamber may have a very little depression in it caused by a chip during the chambering process.When you fire your brass it expands outward into the depression causing a small ridge on the brass that hugs your case.Were not talking about a belt here just a very minute ridge.When you cycle the bolt it is tough to open but once opened it blends the ridge enough that it re-chambers easily.
Lynn

 

[Lynn]

Chino69

Lou
On the Ackley chambers such as a 300 Ackley common to the longrange game it is important to start low and work your way up.The reason for this is most competition type chambers don't have the freebore associated with a factory rifle.
The Sierra Edition V reloading manual lists 84.8 grains of RE25 for use with a 200 grain bullet.If we were to take your advice and start out with a book max load for fireforming to the 300 Ackley we would lock up the bolt and the case would no longer hold a primer at all.
My accuracy load is 75.5 grains and 82 grains is about the upper limit before we start blowing primers out of the cases.We are still 3 grains below book max but we are destroying cases.
As to why most people recommend a book max load and get away with it.If you have your gun in say 223 or 22-250 Ackley Improved your freebore doesn't change.Also most guys are not shooting heavy for caliber bullets meaning there gun is probaly set up for the light bullets.


On the 6BR if you look at the numbers supplied by Twud you will quickly notice he has 0.006 head clearance on a very small sampling of cases.If your first firing is with a max load you will destroy a large amount of your brass.The reason your having success with how your dong it now is your load isn't a max load.I don't know anything at all about your gun but with 30.2 grains of Varget and a 105 Berger your freebore is probaly in the 0.090---0.0112 range and your velocity is hovering around 2830-2850 fps in a 28-30 inch barrel.
A max load with Varget will get you 2970 fps and be very close to 31.5 grains of powder.You will get 10 fps for every 0.1 grains of Varget in a 6BR.
31.7 grains will wreck your brass pretty quickly and 31.5 grains will last 25 firings a long as you start around 30 grains on your first firing.
If you had 200 pieces of brand new brass and loaded up 100 cases at 28 grains for fireforming and the other 100 cases at 31.5 grains the first 100 cases will yield you 97% good cases.The second 100 cases will yield you about 75% usable brass.
If you do indeed have about 0.100 freebore work up to the load I mentioned very carefully and let me know what your targets tell you.
Lynn
P.S. If you go to www.6mmbr.com and look up favorite loads you will see I have been shooting that same load since that website first started.I only say that so you don't question my data on what a max load is.

 

[chino69]

Lynn

Lynn,
Thank you for the clarification; maybe I wasn't clear or precise enough in my original post. The only reason I go to max. load of the parent cartridge when initially fireforming is that I have owned those Ackley calibers previously and have experience with those particular calibers. For example, with my first .22-250 AI I began breaking in the barrel and fireforming by going to the middle of the chart, for a standard .22-250, for my fireforming load. My brass came out with rounded shoulders, etc. and it took several more firings to get the nice sharp shoulders. I kept detailed notes, measured headspace, chrono'ed, etc. I worked up to a pet load that was ultimately approx. 3 grains beyond max. load for a standard .22-250. I wore that first barrel out, threw it's brass out, and had another chambered with the same reamer by the same gunsmith. I bought new brass for the new barrel, neck turned, prepped, etc. When I went to fireform the new brass in the new barrel, I started out with a max. load for a standard .22-250 and my brass fireformed perfectly; nice sharp 40 degree shoulders. I then, from this point, began developing my new pet loads for my new barrel. I was very confident in my methodology because I had been through my initial learning curve. I've used the same process with my .243 AI and my 250 Savage AI and my brass is perfectly fireformed first time. There's no way in hell I would use the same process with a 300 Ackley as I have no experience with that cartridge. I would begin in a conservative fashion with a cartridge of that magnitude and be extra safe. Trust me, I'm not reckless. I really do appreciate your feedback, however, and just want to clarify my position.

With regards to my 6mm BRs, I've developed loads from other trusted shooter's data. I start below their max. loads, working my way up carefully until I find my 'tune'. I know their barrels were reamed with the same reamer by the same gunsmith. I also know what Twud has and the reamer that was used and have been talking to him over the phone to help resolve his issue. Again, thank you for your input. I don't know everything, but when I arrive at a point in my reloading process, it is the end result of careful load development, research, data collection, chronograph data, range data, hot and cold seasonal changes, etc. I'm also open to any criticism, additional info., experience, etc. to make me a more knowledgeable shooter.

The other thing at work here is that volumes of good information is coming in from experienced people trying to help Twud with suggestions, info., etc. We're all trying to help the guy which is admirable but may be a little overwhelming from his perspective. One thing I've gained by following this post is a hell of alot of information I didn't have before or reasons I hadn't considered. Isn't that what it's all about? A group of shooters sharing knowledge, experience, data, and helping a fellow shooter?

Regards,
Lou Baccino

 

[chino69]

Tight bolt

Twud,
How about publishing results, without mentioning names, so that all interested can learn. Interesting that our buddy said chamber roughing would be a viable option if problem had not corrected itself. Please update as I'm interested in other's responses.

Lou Baccino

 

[Twud]

He said that the next thing we could do, had there been a problem, was to rough up the chamber. He'd pull the barrel chuck it in the lathe and go at it with heavy emery cloth.
This whole thing is a mystery. The bolt was tight as hell until yesterday. Now it's smooth as can be. You can guess the dagger thrusts for the next hour.
The gun was cold from the ride in the truck bed, so I brought it in the house to warm up and then I plan on firing it warm. It's the only thing I can come up with. If it's still loose I'm gonna shoot it til the lugs are gone.
Got to watch him ream a PPC chamber. He is an artist, cutting the chamber 010" at a pass. He plays that lathe like a harp.
Mark

 

[Lynn]

Chino69

Lou
Without being there in person it is hard to diagnose what is actually happening.
We don't know if Mark is still using new brass or once fired brass.Using heavy emery cloth on the chamber will make it larger meaning the sizing die is making a bigger reduction on the cases.
Good Luck with it.
Lynn

 

[expiper]

good n tite...

I too have been folowing this thread and agree...there is a lot of collective knowledge/experience being shared....it is a magical thing when you get the right reamer matched with the right resize die and the right brass...as everyone is saying it is difficult to maintain the right ammount of clearance and resize without loosing primer pokets or having bolt "klik",,,It doesnt matter how good the gunsmity is or that the chamber is as strait as Cupid's arrow...if the reamer and the brass and the re-size die are not in concert (a matched set!!)..then nuthin will work.....what a pleasure it is to have everything working like a sewing machine...open, shut--open,shut....then you dont have to think about a thing but the wind...Roger

 

[chino69]

Tight bolt

QUOTE=Lynn;475140]Lou
Without being there in person it is hard to diagnose what is actually happening.
We don't know if Mark is still using new brass or once fired brass.Using heavy emery cloth on the chamber will make it larger meaning the sizing die is making a bigger reduction on the cases.
Good Luck with it.
Lynn[/QUOTE]

Lynn,
That's why I asked Mark to post this info. as I have been speaking with him on the phone and communicating via e-mail to get the issue resolved. The gunsmith involved is one of the better ones in the country. With all due respect to many of you seasoned shooters, this man was in the game when many of you were still buying Playboys at the corner drug store as teen agers.

I had no doubt concerning this man's techniques and would have bet the house on it; I'm that confident in this man's skills. He's the only gunsmith I'll ever use for benchrest quality work and I have proudly referred many other people to him for business. As Mark said, his bolt problem is not a problem anymore. It may have been a small imperfection on one of the locking lugs, or any number of other causes but it was NOT anything this particular smith did wrong, his tecnique, skills, or his reamer. I just wanted everyone following to get that clearly.

Lou Baccino

 

[chino69]

Dagger thrusts

He said that the next thing we could do, had there been a problem, was to rough up the chamber. He'd pull the barrel chuck it in the lathe and go at it with heavy emery cloth.
This whole thing is a mystery. The bolt was tight as hell until yesterday. Now it's smooth as can be. You can guess the dagger thrusts for the next hour.
The gun was cold from the ride in the truck bed, so I brought it in the house to warm up and then I plan on firing it warm. It's the only thing I can come up with. If it's still loose I'm gonna shoot it til the lugs are gone.
Got to watch him ream a PPC chamber. He is an artist, cutting the chamber 010" at a pass. He plays that lathe like a harp.
Mark

Mark,
The dagger thrusts you received were done with a degree of finesse, no arterial bleeding. It's part of the ritual with the gent and necessary to form a good relationship. I've been in his shop when a certain nameless person accused him of not doing his job right and this nameless person, instead of working the problem through with said smith, got in a hissy fit and sent the rifle to another well known smith for resolution. This other well known smith, who is supposed to know what he's doing, compounded the problem. This knowing shooter then went back to our buddy and asked him to correct what the 2nd smith screwed up. Our buddy basically told him to take his business elsewhere because he didn't need him as a customer. The customer had been bad mouthing our buddy in the 'so-called' knowlegeable circles. I say 'so-called' with a degree of rightful sarcasm because none of these 'experts' knew what the hell they were talking about. Had the shooter resolved his initial problem with our buddy, as you rightfully did, his problem would have been solved and he would still be a customer on good terms with said gunsmith.

Those dagger thrusts you received should be worn with pride, similar to a dueling scar. You've earned the man's respect by being a stand up guy and giving the smith the benefit of the doubt. Many people in this game would do well to follow this simple example of proper ethical problem resolution. Now get some loads worked up so that we can whack PA 'marmota monax' this summer.

One travellor to another,
Lou Baccino

 

[chino69]

Dueling scar

Mark,
Congratulations on your dueling scar; we all have them. One thing I've learned over the years is to form opinions over time and back them with as much data as possible before reaching a definitive conclusion. Many times we tend to go with what appears to make the most sense, stop our research, and perhaps miss the real reason something has occurred due to our haste in finding a solution. The other part to this whole episode is there are times when the problem goes away and you just stop scratching your head. If that doesn't work consider the Coreolis effect, unusual sun spot activity, the supernatural or the insidious gravitational effect of a black hole. I'm just having a liitle fun, no foul.

I'll contact you this evening (Monday, Jan. 12th).

Lou Baccino