shortening the barrel of a bolt action...?

S

simonrichter

New member
if I shortened the barrel of a .223 bolt action (1 / 12 twist rate) by one or two inches, would that have a massive impact on accuracy?
 
If done right , it could increase accuracy ! However a 1-12" barrel will pretty much restrict you to bullets 55 Gr. or lighter .
 
If done right , it could increase accuracy !
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How's that? I mean what more can I do than cut it to a certain length, what can be done right or wrong there?

Edit: Just happened to notice that actually it has a 1/9 rate of twist...
 
There would be no practical difference. I think oneoldsap is suggesting that a shorter barrel will be less flexible and therefore more accurate. But any such difference is likely miniscule at best.
 
Shortening a barrel may or may not change accuracy.

Barrel stiffness alone has nothing to do with accuracy. They're all repeatable in how they whip and wiggle for each shot. Repeatability's a key element for accuracy.
 
It might change how accurate your current ammo is out of the gun.

It's possible that you might have to switch to different ammo.
 
You'll lose a little speed. How much depends on the load, how long the barrel currently is and how much you cut off.

Shorter barrels of the same diameter are stiffer, so theoretically more accurate. After cutting the end of the barrel will be recrowned. If done right, and if done better than originally you could see an increase in accuracy. It won't be any worse at reasonable ranges unless something is done wrong.

If you are shooting at extreme ranges you could see loss of accuracy only at the extremes. Once bullets drop below a certain speed they become unstable in flight. Since bullets from longer barrels start faster, they maintain that speed for a slightly longer distance. It might be that from a 22" barrel the bullets will remain stable at 1000 yards. From a 20" barrel they might become unstable at 950. (those numbers were just pulled from the air for illustration purposes, I have no clue what the exact ranges would be)
 
How's that? I mean what more can I do than cut it to a certain length, what can be done right or wrong there?
How were you planning on cutting it?
How were you planning on crowning the barrel?
Or were you going to have it done by a reputable gun smith?
Poor barrel crowning = bad accuracy.
 
The swat people did a test on barrel lengths. They found that no loss in accuracy was achived by shorter barrels as well as no gain in accuracy either. They tested 24 down to 16 inch barrels. No difference. Now as JMR40 stated- Your long range accuracy will be affected,but only because of MV.
 
18" .308

Ive got a FN SPR that had the barrel shortened to 18" and a surefire muzzle break installed.

That thing amazes me in the accuracy dept. Legit 5 shot groups measure .268.

So its basically a 1/4moa gun... Velocity DOES suffer. Even with a 20MOA base on the gun I run out of elevation at about 875 with a 100 yd zero on the gun. After that its all mildot holdover.

I wish i had the gun with the origional bbl length but i got it at a good price. Unless you absolutely NEED the compact version leave the bbl alone and you wont have the distance/velocity issue i do.
 
If done right cutting an inch or two has no practical difference in accuracy OR velocity. What can drastically change is the handling and feel. Personally I don't like any barrel longer than 20", 18" ain't too short.
 
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Just cutting/shortening the barrel shouldn't have much effect (if any) on the accuracy - but failing to make the cut perfectly square to the bore C/L, and/or doing a less than optimal re-crowning of the muzzle surely will effect the accuracy (negatively).



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Just be sure to have it done perfectly (ideally by a qualified gunsmith who has experience re-crowning barrels).

If the cut/re-crown is not perfect, it will affect accuracy (and not in a good way) more so than losing an inch or two. An uneven, non-square cut will result in the gases not being propelled out the barrel symmetrically around the bullet, causing accuracy issues.
 
Me and a freind cut a savage model 12 in 223 down from 26ish to 17" with a sawzall then used a grinder to make the end flush. Then we crowned it with a pointed stone in a dewalt battery drill. It shoots holes in dimes with factory ammo
 
105gr said:
Me and a freind cut a savage model 12 in 223 down from 26ish to 17" with a sawzall then used a grinder to make the end flush. Then we crowned it with a pointed stone in a dewalt battery drill. It shoots holes in dimes with factory ammo
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That's one way to do it, although I doubt many gunsmiths would recommend it. I've seen guys re-crown rifles using a round-head brass screw. Chuck the screw into the drill, coat it liberally with valve grinding compound, and cut a new crown.
 
I've shot the same lot of M852 7.62 NATO match ammo with Sierra 168's through .308 Win barrels 22, 24, 26, 28 and 30 inches long. No visible accuracy difference at 100 through 300 yards.
 
per inch or per two inches?
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You won't know until you put it over a chronograph. Of course, you won't know what it's doing out of YOUR rifle until you put it over a chronograph. Every barrel is different. Trying to deduce factory velocity from your barrel is just an educated guess
 
Me and a freind cut a savage model 12 in 223 down from 26ish to 17" with a sawzall then used a grinder to make the end flush. Then we crowned it with a pointed stone in a dewalt battery drill. It shoots holes in dimes with factory ammo
Click to expand...
Can he also read the dime at the ranges he's shooting it? I kid, I kid ;). No physical reason why a hack-job can't make a good crown, but you are much much more likely to have poor results that way (crooked barrel). What the heck was a 26" 223 intended for, anyway? :confused:

And no one even think about using a pipe cutter on a barrel of any kind; they squeeze too much and will turn a substantial burr on the inside, which if not removed, may increase pressures unnecessarily and tear jackets from bullets (obstruction hazard). Worse in shotguns since they're narrower.

TCB
 
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