• If you are being asked to change your password, and unsure how to do it, follow these instructions. Click here

What barrel contour for chassis

Nuclear Worker

Well-Known Member
Joined
Mar 26, 2018
Messages
638
Location
Fort Atkinson
Looking at building a 6BR for target shooting. Thinking MPA chassis. Might go regular barrel instead of CF. What contour would you use so it doesn't look dumb? Plan on 600 yards max. No place around me with longer range. What length also have a can for it.
 
Looking at building a 6BR for target shooting. Thinking MPA chassis. Might go regular barrel instead of CF. What contour would you use so it doesn't look dumb? Plan on 600 yards max. No place around me with longer range. What length also have a can for it.
PRS Contour
Match Contour

Caliber:6MM
Bore Dia:0.236 Inches
Groove Dia:0.243 Inches
Groove Num:4
Twist Rate:1-7 Inches
Steel:Stainless Steel
Contour Type:Match
Contour Number:M24
Breech Dia:1.2 Inches
Breech Len:2 Inches
Finish Len:26 Inches
Muzzle Dia:0.9 Inches
Barrel Weight:6 Lbs
 
I have shot out a handful of prs comp barrels now. I've done everything from M24, MTU, Hvy Varm, 1.250 straight, and proof comp contour. I think my favorite is a proof comp, which is 1.25 for 7" then straight taper to around 1.00 at the 28" muzzle. I have the 1.250 straight in 6bra, and it shoots okay, but it's been a bit picky surprisingly, my other 2 previous 6bra barrels were all stupid easy to get shooting 1/3 moa at distance. Maybe there is weight to the theory of a barrel needing to be lighter at muzzle VS breech for proper harmonics.
 
When I put a heavy PRS 6mm together, I went with an M24. I also shoot matches suppressed, my can is 7" and so I've gone with 22" barrels on a couple rifles. That puts me about the same overall length and maneuverability as a 26" with a brake. The M24 barrel with the internal weights on the chassis (KRG Bravo) and the external weighted ARCA rail allow the rifle to balance and sit very solidly on a barricade bag and the weight (about 21#) soaks up the recoil so it stays on target. When I built it brass and components were very difficult. I went with a 6 Creedmoor because it was available and I could get large or small primer brass. I couldn't get 105s, so I started out with 115s because they were available and they worked well so I've stayed with them. I'm running them an easy 2830. After I point the bullets, I'm seeing a G7 BC of about .310.

For shooting steel and paper it is a lot of fun, but when I use it for hunting I make sure I park the truck no further than a couple hundred yards from where I'm going
 
Ok I'm a little late to the party.
Look at a MTU or AMU profile barrel. If its a single shot go for the 6mmBR however if it's a repeater don't use any br based case. Look at a 6mmGT they are designed to work from a mag. The br cases can work with an action with a manual ejector however even with br modified AICS mags they are never 100%
 
Since you aren't going to tote or run with it...go with the straight taper.

And I love my MPA chassis.

If you plan on competing, be sure to dig into the rule book for the International Benchrest Shooters. While you don't need a "special" rifle to compete, it is best to know the rules before you build a rifle since there are various classes and disciplines. Thus, optimize your "build" to the class/discipline that interests you.

I had a blast shooting F-Class decades ago. I went from knowing nothing about the sport and just making holes in paper to enjoying competing in matches because of the help and advice of fellow shooters. 99.99% will be eager to help if you just ask.
 
The larger profiles are going to be your friend in competitions like PRS. My latest PRS rifle wears a 26 inch heavy palma Bartlein in 6 creedmoor. This is the 2nd barrel for this rifle. When this barrel is shot out, I will be moving to a heavy varmint or straight 1.25 profile.
PRS Rifle with second barrel.jpg
 
Top