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Bnhpr
12-28-2007, 08:50 PM
I'm trying to come up with a chambering for a general purpose bench rest rifle.

Here's the short list of chamberings I'm looking at. The choices are overwhelming, then start talking about neck diameters... Any experience or opinions on these chamberings is appreciated, feel free to suggest any others.

6mm PPC
6mm BR
.243 Win

6.5x55
6.5 Grendel
6.5-06
6.5x284

30 BR
.308

wnroscoe
12-28-2007, 09:11 PM
Short Range (100-200 LV/HV) for best Agg. = 6PPC
Score = 30BR, 30 wolfpup, 6PPC
600 yard BR = 6-6.5x47 Lapua, 6.5x47 Lapua, 6BR and it's spinoffs BRX etc.
1K = 300 Ackley and simular cartridges & 6.5x284

alinwa
12-28-2007, 09:19 PM
Bnhpr,


"Benchrest" can be divided into 3 broad classifications;

---100-200 yard "group" Benchrest.
---100-200 yard "score" Benchrest.
---600-1000 yard "long range" Benchrest.


Each discipline has rounds tailored to it's particular requirements.



---Short-range BR Group is dominated by the 6PPC, NOTHING else comes in even a very distant second. There are several other options arguably as accurate as the PPC but all of them require specialized knowledge and equipment. For a beginner the PPC is THE chambering of choice.

---Short-range BR Score is dominated by small .30's like shortened .308's. My current opinion is that a 30 cal based on the 6.5X47 case is the case to beat. A subdivision of this score game called "varmint for score" is currently dominated by variants of the 30BR.

---Long-range BR isn't really dominated by anything in particular except that chamberings/twists must throw heavy-for-caliber bullets with accuracy. The various large magnum 30's, the 6.5X.284 and the 6BR each have large followings but there are probably 30 competitive chamberings (a pure-dee guess) in calibers 30/6.5/6mm. I wouldn't consider any other caliber than these three.


The closest you could come to covering all of these bases with one chambering would be a 6BR IMO. If you bought a 6BR reamer spec'd with a .271 nk, .030 freebore and had two barrels fitted you could have a rifle set up to honestly compete in all three disciplines.


al

f d shuster
12-28-2007, 09:35 PM
bnhpr: My first dedicated bench ctg. some years ago was, of course, the 6ppc. .262" neck. Lapua brass w/ the req'd neck turning. Outstanding groups, as expected. Then had 2 6BRs' built ( Shilen & Hart ) both w/ .265" necks. Lapua brass w/ neck turning. Accuracy close to, or sometimes "as good as" the ppc. Next on the list was a 22BR .251" neck (Shilen 1-12), excellent w/ more neck turning. My latest venture has been a Savage mdl 12BVSS .243 set-back & rechambered to 6BR with a .272" no turn neck. The results have been so outstanding with the factory Savage barrel ( 1-9.25 twist ) I've never regretted the "conversion". An excellent load has been 32.5 Varget w/ Sierra 75 gr. #1510 (a varmint, not match bullet ). Doubt I'll ever have another tight neck chambering. The Pacific reamer is mine, so the next high-grade barrel will be cut with that reamer. Just my humble opinion: you'll probably get a lot of first-class advice from others more knowledgable than I.:)

Bnhpr
12-29-2007, 01:13 PM
bnhpr: My first dedicated bench ctg. some years ago was, of course, the 6ppc. .262" neck. Lapua brass w/ the req'd neck turning. Outstanding groups, as expected. Then had 2 6BRs' built ( Shilen & Hart ) both w/ .265" necks. Lapua brass w/ neck turning. Accuracy close to, or sometimes "as good as" the ppc. Next on the list was a 22BR .251" neck (Shilen 1-12), excellent w/ more neck turning. My latest venture has been a Savage mdl 12BVSS .243 set-back & rechambered to 6BR with a .272" no turn neck. The results have been so outstanding with the factory Savage barrel ( 1-9.25 twist ) I've never regretted the "conversion". An excellent load has been 32.5 Varget w/ Sierra 75 gr. #1510 (a varmint, not match bullet ). Doubt I'll ever have another tight neck chambering. The Pacific reamer is mine, so the next high-grade barrel will be cut with that reamer. Just my humble opinion: you'll probably get a lot of first-class advice from others more knowledgable than I.:)

I see that PTG has a 6mmbr reamer with no-turn neck in Midway. With that Savage, roughly, how much of the barrel did you have to cut to get down to 6mmbr? Does it really shoot that good? A Savage, with a factory barrel? Did you do a lot of action work?

Thanks,

Ben

caroby
12-29-2007, 09:18 PM
The closest you could come to covering all of these bases with one chambering would be a 6BR IMO. If you bought a 6BR reamer spec'd with a .271 nk, .030 freebore and had two barrels fitted you could have a rifle set up to honestly compete in all three disciplines.
al

Yes for an all around solid "general purpose BR chambering"...
Freebore choises... 1-12 - 1-14" twist barrels .030 is fine (shorter bullets)...
1-8" - 1-10" twists go with the longer free bore .050 - .090 freebore, you'll need as much room for powder as possible with the long heavy 6mm pills.

The 6BR Norma .271nk chamber mill be a well used reamer....!;)
cale

AVanGorder
12-29-2007, 09:33 PM
I'm trying to come up with a chambering for a general purpose bench rest rifle.


What type of shooting are you thinking about doing? BTW, where are you located?

Bnhpr
12-30-2007, 09:13 AM
What type of shooting are you thinking about doing? BTW, where are you located?

I'm located in mid coast Maine, and thanks to some folks here encouragement/criticism, I'll probably attend several of the matches scheduled in 2008, around my house. There are 4 matches for score shooting within 1.5 hour drive of me, in 3 locations. (100-300yd/mtr)

I kinda would like to build a rifle that meets the hunter class and Varmint hunter slass scrutiny of 10 lbs and case capacity >45 grH2O with the 6mm BR.

With the 100-300 yd/meter courses of fire, this seems to make the most sense for me to get into H and VH to start shooting competetively in the score matches.

The Varmint for score LV and HV allows a 10.5 or 13.5 lb rifle. Now, in my simple way of thinking, the 13.5 lb limit is best used with a slightly wider stock, and as heavy a bbl I can get and meet the size/weight criteria. And the 10.5 lb LV limit I would have a similar barrel contour to the Varmint hunter class, just a wider stock. So, I see no advantage in building a LV rifle, since it would not meet the VH class anyway?

So, no matter how you cut it, I should have two rifles to compete in all 4 classes in score shooting. Obviously, I'm selling myself short if I enter a 10 lb hunter class rifle, which has a 2.25" stock, in a 13.5 lb 3" class. The varmint class also allows and case capacity, so I have the option of 6mm PPC in the varmint disciplines.

Rifle 1

Hunter class/Varmint hunter class 6mm BR, neck/freebore/twist TBA.

Rifle 2

Heavy Varmint classed rifle (<13.5 lb/<3" flat forend), chambered 6mm PPC


All feeback appreciated.

pbike
12-30-2007, 09:35 AM
Rifle 1 will not fly, for Hunter class 45 grains water weight load is needed and 6BR wont do it. 6 BR or .30BR will work for Varmint hunter class though, and switching the barrel to a 6 x47 Lapua, or .30 x 47 Lapua will meet the watewr weight rule. Keep in mind there has to be provisions for a magazine, and that rifle only has a 6x scope.

Rifle 2, I would build for Light Varmint, if you choose to also shoot groop matches, the LV will shoot in both HV and LV classes where the HV won't. Also I dont believe that shooting a LV against HV guns is much of a Handicap, if at all. There is a new movement of shooters that are shooting both LV and HV for score. There are different State, and National records for LVFS and HVFS. in shooting VFS you are all competeing together, but if you break a record, it matters what gun you are shooting. I don't worry about that, I shoot to win the match, and if a record falls so be it.

Paul

f d shuster
12-30-2007, 10:01 AM
bnhpr: In answer: the original 26" factory barrel is now exactly 25 1/16". I'm limited to further set-back by the thread dia., and still be able to use the barrel nut. Further set-back would result in the threads (on the barrel) having "flats". Yes, it does shoot. Best group to date has been .531" w/ 5 shots @ 200 yd. Overall I've been able to hold 1/2 moa w/ 5 shot groups @ 200. With my "Hawkeye" borescope it has the typical reamer marks across the lands & grooves. Copper fouling was heavier, and more difficult to remove when new, but after 600 rds., with "Butchs", coppers a LOT less and is easily removed. Action was not altered in any way. My freebore on the PTG reamer is .080": I would have preferred .040" to .060", since I mainly use max bullet wts. of 87 gr., but I can live with it. The .080" reamer was in stock and I did not want to wait for another.

henrya
12-30-2007, 11:39 AM
With 4 ranges shooting Score nearby I'd build a 13.5 pound HV .30BR without a second thought. One rifle is plenty to get you started especially if you attend all those matches. Sounds like you could shoot almost every weekend and stay close to home. Shoot that one rifle and barrel a bunch through the year and you will likely perform better than if you switch around with different cartridges and rifles.

Later on you could add a 6PPC barrel if you wanted to have a better more mainstream Group rig - if that appeals and you decide to attend those matches.

I am new to BR competition but I can clearly see that its a very specific game and if you want to do well you better have a specific rifle to best do the particular job. Its really the same in most organized shooting games. The rules and game are long established and for years folks have built guns to suit those rules. Its mostly all worked out for you. You wouldn't bring a trap gun to a skeet shoot and there is no point in showing up with a rifle that is not built precisely to the purpose of the BR game you choose.

Bnhpr
12-30-2007, 07:50 PM
bnhpr: In answer: the original 26" factory barrel is now exactly 25 1/16". I'm limited to further set-back by the thread dia., and still be able to use the barrel nut. Further set-back would result in the threads (on the barrel) having "flats". Yes, it does shoot. Best group to date has been .531" w/ 5 shots @ 200 yd. Overall I've been able to hold 1/2 moa w/ 5 shot groups @ 200. With my "Hawkeye" borescope it has the typical reamer marks across the lands & grooves. Copper fouling was heavier, and more difficult to remove when new, but after 600 rds., with "Butchs", coppers a LOT less and is easily removed. Action was not altered in any way. My freebore on the PTG reamer is .080": I would have preferred .040" to .060", since I mainly use max bullet wts. of 87 gr., but I can live with it. The .080" reamer was in stock and I did not want to wait for another.

I was wondering if you kept the nut. Is there any reason to keep it besides headspacing?

Did you use a solid pilot reamer? Did you bore the chamber or use a roughing reamer.

Thx.

Ben

f d shuster
12-31-2007, 12:59 AM
bnhpr: Yes, kept the nut. When this barrel is shot out, will re-place it with a pre-fit Shilen, Pac-nor, etc. I want to keep the ease of replacement & swapping. My reamer is a live pilot. All cutting was done with the PTG finish reamer. RPM kept very low with frequent cleaning breaks for chip removal. With the before mentioned tight fitted necks, this is my first "no-turn". Loaded round neck dia.is .269" with Lapua, so I've got .003" total clearance. My .265" chamber neck dia. 6BRs' (Shilen & Hart), both use Lapua with loaded outside neck dia. of .264". Both these chambers were cut with the same reamer, back to back, so they are as identical as possible. Ammo can be swapped between both, except for small noted preferences due to Shilen vs Hart barrels. Ex: Shilen wants all bullets to touch, and Hart prefers .020" jump. My 22BR loaded neck dia. is .2495"/.250" with Lapua. After all the hours spent neck turning ( not "fun"), it's so nice to just be able to load-em like any other brass/chamber combination and go shoot! And the neck dia. is still smaller than "standard", so no overworking of brass with accelerated hardening of the case necks. I know neck turning works, but matches are being won with "no-turn" necks. Have a Happy New Year.:)

hecksf
01-01-2008, 07:24 PM
If you want a rifle to shoot off of a bench, then yes the choices can be overwhelming.
BUT! If you want a Bench Rest rifle then the choices are a bit narrower.
Ted

greg
01-01-2008, 08:22 PM
I'm located in mid coast Maine, and thanks to some folks here encouragement/criticism, I'll probably attend several of the matches scheduled in 2008, around my house. There are 4 matches for score shooting within 1.5 hour drive of me, in 3 locations. (100-300yd/mtr)

I kinda would like to build a rifle that meets the hunter class and Varmint hunter slass scrutiny of 10 lbs and case capacity >45 grH2O with the 6mm BR.

With the 100-300 yd/meter courses of fire, this seems to make the most sense for me to get into H and VH to start shooting competetively in the score matches.

The Varmint for score LV and HV allows a 10.5 or 13.5 lb rifle. Now, in my simple way of thinking, the 13.5 lb limit is best used with a slightly wider stock, and as heavy a bbl I can get and meet the size/weight criteria. And the 10.5 lb LV limit I would have a similar barrel contour to the Varmint hunter class, just a wider stock. So, I see no advantage in building a LV rifle, since it would not meet the VH class anyway?

So, no matter how you cut it, I should have two rifles to compete in all 4 classes in score shooting. Obviously, I'm selling myself short if I enter a 10 lb hunter class rifle, which has a 2.25" stock, in a 13.5 lb 3" class. The varmint class also allows and case capacity, so I have the option of 6mm PPC in the varmint disciplines.

Rifle 1

Hunter class/Varmint hunter class 6mm BR, neck/freebore/twist TBA.

Rifle 2

Heavy Varmint classed rifle (<13.5 lb/<3" flat forend), chambered 6mm PPC


All feeback appreciated.

you plan to shoot in Maine there are only score shoots being offered at this time, and for the immediate future. You will be seriously outclassed if you decide to build a PPC, either light or heavy. Everyone who has, has reconfigured their guns to some form of 30 caliber, usually the 30BR. It makes no matter whether you build it as a 13.5 or a 10.5 lb gun, either will shoot competetively in the varmint for score class but the 13.5 lb gun will be much softer on your shoulder. Regarding stock config, if its a VfS gun, make it a 3" wide forend. The Kelbly Klub, Borden, Edge are all good choices. If you plan on using a heavy scope like a Nightforce then you will need to build the gun around the scope so component selection and weight become critical.

Regarding a Hunter gun, if you want to compete in the Hunter class (vs the varmint hunter class) you will need a 30 caliber, 10 lbs max including scope and the case capacity has to be greater than 45 grs water...30-30 size. There are stock configuration limits but any good benchrest gunsmith will know this. It's also in the rule book online. Do yourself a favor and build a Hunter class legal gun. There are few 6 power shooters and fewer that shoot varmint hunter class.

In the end the 30 caliber hole just outclasses the 6mm hole. --Greg(Eastern Maine)

AVanGorder
01-01-2008, 08:49 PM
Here is what I suggest....

Start with whatever you have. Do you have a factory rifle of any type? Go to the matches, shoot them with what you have (or can borrow). See what the other shooters are shooting, speak with them in person, you'll learn so much more than you think.

Bnhpr
01-02-2008, 10:07 AM
you plan to shoot in Maine there are only score shoots being offered at this time, and for the immediate future. You will be seriously outclassed if you decide to build a PPC, either light or heavy. Everyone who has, has reconfigured their guns to some form of 30 caliber, usually the 30BR. It makes no matter whether you build it as a 13.5 or a 10.5 lb gun, either will shoot competetively in the varmint for score class but the 13.5 lb gun will be much softer on your shoulder. Regarding stock config, if its a VfS gun, make it a 3" wide forend. The Kelbly Klub, Borden, Edge are all good choices. If you plan on using a heavy scope like a Nightforce then you will need to build the gun around the scope so component selection and weight become critical.

Regarding a Hunter gun, if you want to compete in the Hunter class (vs the varmint hunter class) you will need a 30 caliber, 10 lbs max including scope and the case capacity has to be greater than 45 grs water...30-30 size. There are stock configuration limits but any good benchrest gunsmith will know this. It's also in the rule book online. Do yourself a favor and build a Hunter class legal gun. There are few 6 power shooters and fewer that shoot varmint hunter class.

In the end the 30 caliber hole just outclasses the 6mm hole. --Greg(Eastern Maine)

Thanks Greg,

I will be building the rifle myself from an action and barrel blank. I have been looking for some ideas of Hunter and varmint hunter guns. This was also recommended to me from a fellow that sent me a PM. I have a .308 match reamer, and maybe that's the way to go for these classes. I really like the 6.5x47 Lapua, but everyone is trying to shy me away from smaller bullets in score shooting. I guess the bigger bullets make the difference because of hole size. How 'bout 35 Whelen or some of the heavy hitters? Does anyone do that in Hunter class? I will need to go to many shoots before I invest the money in VFS class rifle. I've talked with some heavy hitters already that come up to the Maine matches. Those guns that Jim Borden makes, and all, look really sexy. I would be embarrassed to put some piece of Junk up against those beauties. LOL.

Ben

AVanGorder
01-02-2008, 10:21 AM
Those guns that Jim Borden makes, and all, look really sexy. I would be embarrassed to put some piece of Junk up against those beauties. LOL.

I just completed my second year of shooting VFS. I had, without a doubt, the ugliest gun, ever, at the bench. The stock started life as a right handed Baby Shehane. It ended up on my left handed Viper. It had been cut on, widdled on, whack on... to make light weight. Every time the trigger was pulled it would torque so badly that it would almost come out of the front rest. It kicked like a wild zebra and would only shoot right if it was shot totally free recoil. The finish was a mess (I kinda miss it :-) )

Everyone lovingly called it "The Ugly Gun".

However, it worked!

Adrian

Boyd Allen
01-02-2008, 10:35 AM
As to your .35 caliber question, no one makes bullets in that caliber of suitable quality. Your .308 match reamer probably has a throat that is too long for the short bullets that are so popular in the sports that you mention. If you want to cover both HBR and VFS events you might look at the .30 x 47. With the proper throat length and rifling twist, it would probably get you started in both. You will be switching scopes depending on which type of event you are shooting.

glp
01-02-2008, 02:05 PM
Thanks Greg,

I will be building the rifle myself from an action and barrel blank. I have been looking for some ideas of Hunter and varmint hunter guns. This was also recommended to me from a fellow that sent me a PM. I have a .308 match reamer, and maybe that's the way to go for these classes. I really like the 6.5x47 Lapua, but everyone is trying to shy me away from smaller bullets in score shooting. I guess the bigger bullets make the difference because of hole size. How 'bout 35 Whelen or some of the heavy hitters? Does anyone do that in Hunter class? I will need to go to many shoots before I invest the money in VFS class rifle. I've talked with some heavy hitters already that come up to the Maine matches. Those guns that Jim Borden makes, and all, look really sexy. I would be embarrassed to put some piece of Junk up against those beauties. LOL.

Ben
it matters not what the gun looks like but how it shoots...and how you shoot it :). There are many proven componenet combinations that work. What won't be competitive is an non-accurized Remington action. Generally Winchester actions are considered a bit too heavy and complex to accurize. Mauser actions are just not shot much in competition. What you may want to consider is a used gun. Unless you know the owner, consider the used gun to need a new barrel and price it accordingly.

The 30 caliber guns outclass the smaller calibers because the chambering(done by a good gunsmith) is accurate and the bullet is bigger. The 6.5 mm suffers from few really good competition bullets. Bullets and brass are two components you want to keep in mind. Pick a caliber that has a good selection of custom bullets available. 6mm does, 30 does also. 7mm and 6.5 don't. The trend today in 30 caliber is light bullets..112 to 120 grain. The .308 is a fine cartridge. However, it burns a lot more powder and generates more recoil than say a 30BR or a 30x47 on the new 6.5x47 lapua case. Look before you leap. Good luck and hope to see you a some shoots in the Spring.