.260 Barrel Length?

[Leddy]

How short can one go on a .260 build and not sacrifice Velocity? Gun will be suppressed if that matters in answer.

Also reading that a 1:9 twist is best for this round.

Action is in hand and the Short Action thread has me on the .260. Planing ordering barrel before to long and just trying to make it a good one.


Thanks for help

Led

[-HIC-]

How short can one go on a .260 build and not sacrifice Velocity? Gun will be suppressed if that matters in answer.

Also reading that a 1:9 twist is best for this round.

Action is in hand and the Short Action thread has me on the .260. Planing ordering barrel before to long and just trying to make it a good one.


Thanks for help

Led

Shorter will loose velocity in most finished barrel lengths. Without getting into all that, I will just say that for me 24" is about as long as I am comfortable hunting with a suppressor attached. And for that caliber is not a bad choice un-suppressed if you plan to shoot both. However, the 24 will not have as much MV as say a 26 or 28. *Edit* assuming same load, conditions, etc.**

There are plenty of online resources for powder burn, MV, etc. for the .260 barrel lengths if you care to get into that.

[Slick8]

You'll likely loose about 25 fps per inch you remove. I have two rifles that I bought / built specifically for suppressors. One is a 20 inch 308 and the other is a 22 inch 22-250AI. They've both met my goals of 2700 with a 168 and 3-3100 with an 80 grain respectively.

When building a rifle for such purposes, it's a compromise. Do you want a long barrel that will get really long with a suppressor or do you want a shorter barrel that will handle better with the can. First decide what your goal is and build a rifle that will deliver the goal.

You'll loose a little MV but not all that much. You could gain a little back by going with a 260AI in a 22 inch barrel. Plus I'm an AI NUT, just a better design IMO.

Also, as you're going to give up a little MV, I'd recommend going with a 1:8 twist to compensate for the slightly less MV. It will easily run a 120-140 out of that 1:8.

To answer your question, I'd go no less than 18 and likely go 22. Remember the more you reduce bore diameter the less efficient your cartridge is so you may also wish to consider a 7mm-08 or the trusty ole 308.

[kmon]

A lot depends on what you are planning to do with the gun and how far you plan to shoot. adding a suppressor like -HIC- said will add some of the velocity back and make the blast from a shorter barrel not nearly as bad. Legal min for a short barrel without another tax stamp is 16 inches and I know of some. If it is a hunting rifle used inside 500 yards using a good dial up scope for elevation correction 16 to 18 works and makes the suppressor equipped rifle a lot handier from a stand or truck. For twist rate going I would definitely use 1:8 twist for a 6.5 build. Look at the Berger twist rate calculator with the long 140gr and above at 260 velocities you are marginally stable with them loosing some BC. You might get a few more fps with the 1:9 but not enough to justify. I have a couple 6.5 barrels at 1:9 and do loose a little BC with them.

I hunt a lot with a factory 7mm08 at 18.5 inches.