Shorter Barrel = Faster speed

Saw this video today about the Tikka TAC A1 and at the 1:55 mark he talks about not getting the speed out of Tikka's 24" barrel so he put a 22" Bartlien barrel on it and gains 115 fps.

How does the same ammo produce a faster speed out of a shorter barrel made by a different manufacturer?

https://www.youtube.com/watch?v=shqciW9BgSo

Every barrel is unique and produces difference results.

I'm gonna make an educated guess.

Cut rifled verus button rifled.

What was the twist rate of each? A more agressive twist can reduce velocity.

Did each barrel have the same round count? At least, were both north of 250 rounds, which is where most 6.5mm settle in.

Could also be due to the chamber.

Tighter bore, which creates more pressure.

this^^^ is most likely the answer... just watched the video there are tons of difference between those barrels

Custom vs mass produced barrel? Even though Tikka/Sako are about the best when it comes to factory barrels.

Nope. Not a factor in and of itself.





Correct.

Actually the Tikka CTR barrels are pretty widely known to be on the slow side. They shoot like lasers, but tend to give up some velocity.

Have you seen the tool chatter inside both before?

I didn't watch the video (blocked here at work) generally speaking a shorter barrel will not yield faster speed. There are other factors...my first two guesses without knowing anything about the issue is 1 - tighter bore as mentioned above...item that popped in my head initially that wasn't mentioned is freebore will effect pressure/speed/etc.

One of them is a Bartlein, and one of them is not. That’s how.

I have a feeling that researching the gain LH twist thing would make my brain hurt.

^^^Agree^^^ any factory barrel settled in or not can't compare to a Bartlein, two different animals. It's not worth breaking out the measuring tape, that's why I cringe when someone starts talking about brand X is just as accurate as any semi custom or fully custom rifle thats custom chambered by a reputable smith. The only way to get precision accuracy is to have a precision rifle built then develop a custom hand load.

So if it was pressure then the 24 inch could have been loaded to match or exceed the speed of the shorter barrel.... only makes sense.

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This for sure.

Idk about tool marks but there are some serious shooters/builders over in the benchrest world that swear Broughton button barrels are faster than most other custom barrels.

Was going to be my thoughts as well.

Lots of things come into play when talking rifle to rifle, barrel to barrel. Chamber size, throat length, barrel diameter and consistancy, type of rifling, smoothness of bore, land and groove style depth etc. That is not a complete list. We are quessing and so is anyone else that says they have the for sure truth of cases like this.

Thanks for all the responses and education. I done learned something today!

Tighter chamber of a custom barrel makes sense as well as the smoothness of the bore. Didn't realize barrels would gain speed as they settle in.

^^yep^^ Broughton's are known/said to be faster I don't have one but I know two smiths that have built and re-barreled alot of rifles and both say the same about Broughton barrels.

I know, I know! They oiled the barrel on the 22 incher! Yeah, that's it - less friction.

Yep. If you do it right there is none. I've borescoped a pretty decent number of Hardys, and they're some of the most perfect bores you will ever see.

How bout a Remington, Tikka, or Savage? Worse I ever saw was on a friend's Thompson Encore. It could be seen with the naked eye.

Yeah, I believe that. My point was more that Button vs Cut doesn't make that difference in and of itself. Doing it properly does.

No argument from me.