New barrel

[rudy16]

I just received a new Bartlien barrel and am getting ready to order a reamer. The specs are 6.5 cal with a 8.5 twist. How do I figure what
grain of bullet I want to shoot. How do you what grain of bullet will best suit the twist rate.

 

[holstil]

I think, people will buy a barrel based on what discipline they are going to shoot in first. There will be a particular couple of bullets that tend to perform well for that purpose. A bullet and speed are chosen based on desired characteristics such as recoil, cost of materials, and availability of quality components. That would kind of tell you what length barrel and twist rate you need to accurately shoot your bullet. And then profile is thought out for weight restrictions.
I only say this to offer insight on future barrels.
To answer your question, you will be looking for the heavier bullets like the 142SMK if your shooting paper downtown. Typically, you only want as much twist as is necessary to stabilize the bullet. Faster twist barrels like the 8.5 will stabilize heavier bullets for long range.
As far as I know, experience is the best way to know what is the best bullet barrel combo. I have never seen a chart, but I know the info found on this site will get you what you need to know.
Take care, Jim

 

[fdshuster]

rudy16: Yes to what Jim said about bullet and twist: Had my first 6BR done with an 8 twist, and decided I wanted to stay in the area of 95 gr. bullet weight. Chose the 95 gr. Berger VLD, seated that bullet in a new Lapua case with the base of the bullet very close to the bottom of the case neck. Measured the loaded round neck dia. and got .269", so a .272" no-turn chamber neck was specified. Chamber length was at 1.570", .010" longer than max case length on a 6BR. Put it all together on a drawing, included the "dummy" round, and sent it off to Dave Kiff/Pacific. He determined the proper throat depth using the "dummy" round, and cut the reamer to meet all my specs. That reamer has cut 2 chambers so far, more on the way.

 

[sxsboy]

Frank is 'right-on" about having your reamer made up at PTG. I know very little about what makes up a good chamber but I have sent a dummy round to Dave on two occasions and told him what I want. When the reamers showed up and I chambered the barrels I could not be more pleased with the out come. A 22-250 I made up w/ a shillen barrel, I can push the spent cases into the resize die with my thumb. A 308 chamber in my 1903-A3 with a Krieger barrel set up for 155gr Palma bullets can shoot 1/2 MOA @ 100 with open sights. PTG (Pacific Tool and Gauge)is one of the best companies you could deal with in the shooting industry. Everyone I've ever talked with there is knoledgable and very helpful and once you go the "make up exactly what you want to shoot and then have the reamer set up for you route" there will be no turning back. ;D

 

[Rust]

A 6.5 barrel with a 1-8.5 twist should stabilize everything up to and including the 139-142 gr match VLDs which leaves you with the choice of everything in 6.5. So, are you planning on shooting short range, 1,000 yard or what, as THAT is what would really determine your choice of bullet.

Once you settle on a bullet suitable for what you want to do, load a couple of dummy rounds with that bullet seated to where you want it and send them to your reamer maker to have a reamer ground to match. If you are considering a tighter than SAAMI spec chamber neck diameter, that would be the time to spec that too.

Plan before you jump, less expensive that way and a better chance of happiness.