22 Barrel length

[Henpeckd]

seems to be a lot of opinions about the optimum barrel length. It seems semi auto rifles seem to have shorter ( that is 16 - 18" ) barrels than bolt action ones ( 20-22 ) . What are the pros and cons of length on accuracy ? What other factors are in play here. I would accept a referral to a thread that has explained this trade off , but hopefully it is more than just somebody's opinion.

[alpha_romeo_XV]

Twist rate and bullet weight come into play. There isn’t a big range in 22LR bullet weight (compared to some centerfire calibers). 40 grain most common, and 36 or 38 for higher velocity. I have a couple boxes of the “sniper” subsonic 60g from Agulia.

1 twist in 16” in with a 16” barrel is accepted as sufficient to give accuracy with a 40 grain 22LR.

I have a 16” CZ barrel that is very accurate but I need a 4X scope to obtain it, since my eyes can’t focus on a front sight that close.

Going with iron sights a longer barrel gives you a longer sight radius even with good eyes but with mine I can see the front sight post at 24” on my Marlin.

Sight radius = human factor vs. barrel length + twist rate = ballistic factor

[Switchbarrel]

Having just gone through this, I will forewarn you that there is very little ACTUAL information to be found. Lots of anecdotes, "I heard..", "I read a long time ago...", "Some magazine...", etc. I wanted to see actual barrel cut down testing results. Nobody could point me to actual testing. I think I found one college student who did one for a school report & that website ballistics by the inch. I asked both KIDD & Beyer barrels if they'd done any cut down testing & was told "no". A little surprising since they both sell different length barrels.

Found a couple tests where they used different rifles with different length barrels for ammo testing but this doesn't tell you anything useful. I've got different barrels of the same length & they have different velocities, much less trying to correlate barrels of different lengths from different manufacturers.

Built a 10/22 for my wife & daughter to shoot silhouettes out to 100M. So, I was concerned with both velocity & accuracy.

Good luck in your quest, post links if you find anything useful.

-Rick

[xrMike]

http://www.ballisticsbytheinch.com/22.html

[bphage]

Last I recall Kidd stated the 18" bull barrel was most accurate but primarily due to weight. So i bought that and just actually posted my home receiver build findings. I think I can tighten up the groups though. My kids and wife have carbon fiber barrels. I have yet to find anything that really looks a length of the same barrel. It seems to me that velocity would not be helpful unless we had supper accurate ways of measuring velocity to show consistency which is what will define accuracy from a velocity standpoint. I spent a whole lot of money on these 10/22s and they shoot well. Here was the carbon barrel I used and is near as accurate as the kidd:

http://www.midwayusa.com/product/422271/magnum-research-magnum-lite-barrel-ruger-10-22-22-long-rifle-920-diameter-1-in-16-twist-17-carbon-fiber-black

Given I have three identical rifles other than the stock colors I found that the tightest fitting stock shoots the best and seems to be about .5 moa at 50 yards with target cci. I have not taken the carbon barrels out to 100 yards.

[ThatFishGuy]

I'm trying to find a review I had read, but it compared the savage fv-sr and the trr-sr models. One has a 16" bbl and the other is 20-22" i dont remember which. Anyways, same action and rifling type. Velocity tests with several types of ammo yielded the same results: the 16" bbl achieved the same speeds as the longer one and showed equal accuracy. Now I'm sure with variances in manufacturing and rifling methods, there will be slight differences but it seems that complete burn is achieved within first 16" of barrel. So i'd say that 16-18" is all you need for top velocity. But like others have stated, longer barrels offer a longer sight radius if you're shooting irons.

[LynnJr]

The world's finest 22 lr gunsmith has a website at

https://WWW.wwaccuracy.com

I doubt he has ever worked on a semi auto but he dominates the 22 Benchrest scene.
Go to the Benchrest forum and ask Bill Calfee what barrel length he would use if he had a perfect barrel.
He evaluates each barrel before cutting and crowning using slugs to determine where the chamber and crown will be cut regardless of the length. That said he still has length limits before your blank gets sent back for a replacement.
If it's for a semi auto the length doesn't seem to be as important as the chamber. The more engraving the better from my limited experience.
Here is his book and one of his paintings. Truly one of the best gunsmiths ever and an honor to be mentioned in his first book.