6.5 prc build?

[volunteer06]

I am finally getting ready to do my first custom build and have read and gained alot of knowledge from the people of this form and want to thank everyone for that.

I know the 6.5 prc has been beat like a dead horse on here but I'm still left looking for some advice. I currently have a bergara in 6.5 prc and am liking it a lot. Fills the needs I'm looking for on first build.

So first question I am planning on running the 156 in the build and see a lot using 7.5 twist and some even saying 8 twist. Is there any down side to a 7 twist? I may have went ahead and ordered an x caliber carbon while on sale and they only do the 7 twist. I thought it would be fine but haven't saw many people running that fast. Plan on it finishing at 26" and using rl26 I'm thinking I will be close to 3000fps does that seem close?
Also what ammo boxes is people running setting these out long I picked up some Frankford arsenal 515 for 270 & 300 wsm they won't shut with 147 set out long. Thanks

 

[Recon$$]

Think you will be just fine with a 1:7.

 

[highdrum]

Zero need to over spin your bullets. 8 twist has stabilized 156s in creed, saum, prc, everything at my 2000' elevation from 0 to 90° only go 7.5 or 7 if you will run solids.

 

[snox801]

The 1/7 will be fine and if I was to do it again I would do just that. Mainly as stated above I could run the heavier hammer or cutting edge mono with no downside to lead

 

[Montana73]

The majority of 156gr 6.5 PRC users recommend 1:8 and fine for 140's as well.

 

[Kmccord]

You will need to verify the speed you plan to run it at or what you believe you can reach to see if you are going to overspin the bullet to cause it to explode in flight. This happens with cup and core bullets, the solids like Hammer, Cutting Edge, etc., those require a faster twist keep them stable during flight, they are longer bullets to reach the same weight as the cup and core.

 

[Rhett Crider]

To answer your 2nd question, I use MTM RLLD-50-10 flip top or MTM J-20-MLD for 20 rounds. My PRC load is 3.027 OAL so just outside short action.

https://www.mtmcase-gard.com/common/Rifle-Ammo-Box-Chart-MTM-Web.pdf

 

[can1010]

another good box is Berrys. there special box model 415 will take up to 3.2 OAL.

dont overspin the bullets to many problems
1-8 for cup & core
1-7 for copper

 

[snox801]

I don't think he would be over spinning a 156gr like he stayed with a 1-7.
If I was to do my creedmore over I would do a 1/7 instead of 1/8 because I've never shot anything less that 140gr cup and as heavy as I could go with hammers is 124gr. The 1/7 would be well suited at the 147-156gr cup core

 

[can1010]

the Hornady bullets have real problems with over spinning and you dont want to limit yourself on bullet choices
also his choice of barrel manufactures while good will have a better chance of problems compared to others

 

[Painless300]

I'm shooting 156's in the PRC on a mid action, my chamber is Saami spec. and barrel is 22" 1/8twist. Running 59.5g of H1000 and getting 2915. I think 3000 is achievable in a 26" with the right powder.

 

[Kmccord]

Here is the formula and what I was getting at on over spinning, keeping the bullet below 300,000 RPM's.

Rifling - Twist Rate - Bullet Revolutions Per Minute (rpm) | Bullet Revolutions Minute (rpm) | Technology Trends

 

[can1010]

muzzle velocity x 720 divided by twist rate = RPM
both ways will get you to the same place this is the one i have always used

 

[Hard rock]

muzzle velocity x 720 divided by twist rate = RPM
both ways will get you to the same place this is the one i have always used

I've got both 1-7.5 and 1-8 twist if I had it too do over they both would be 1-7.5 or 1-7.5 and the other faster the throating on mine is .145 versus the.188 so I can seat out too the lands if needed and still have room in the mag box the throat will grow in a few hundred rounds the early throating was .130 do a little research and get it right the first time I use the Curtis bottom metal same inlet has the Hawkins good luck