Experiences with 3-Groove rifling in .223 (.224)

[amlevin]

I've been reading a lot of older posts across the "net" regarding 3-groove rifling and .224" bullets.

Some say "OK if you keep the speed down" and others say "No way, they damage the jacket so bad that the bullet won't even reach the target".

I have a new barrel currently on order in .223 cal with a 3-groove, 1:7 twist, canted rifling. I would like to be able to launch 90gr Berger VLD's. Even with the extra length (26") I don't think I'll see speeds much above 2600-2700 fps.

Has anyone had some CURRENT experience with a 3-Groove and the 90 gr Berger VLD? I'm interested in your experiences, good or bad.


Thank you to all of you that would like to chime in and tell me I should use another bullet, twist rate, etc, but my question is very narrow. 90 gr Berger and 3-groove 1:7 .223.


BTW, when I contacted Berger with the same question they responded with some load data and the statement "You shouldn't have any issues shooting these bullets with that barrel. Do those that have done so feel the same.

 

[LitLBoy]

I shoot Lilja 3 grooves on all my rifles. A 223AI, 50gr. Blitzking 3600 fps and a 20 practical with 39 gr. blitzkings @ 3700 fps. From the look of the PD's the bullets are getting there just fine. The same can be said for the 221FB -- 6XC --- and 6.5CM
LitLBoy

 

[amlevin]

I shoot Lilja 3 grooves on all my rifles. A 223AI, 50gr. Blitzking 3600 fps and a 20 practical with 39 gr. blitzkings @ 3700 fps. From the look of the PD's the bullets are getting there just fine. The same can be said for the 221FB -- 6XC --- and 6.5CM
LitLBoy

What twist rate(s)?

 

[Keith Glasscock]

I haven't yet tried 3-groove in .224 I don't understand why it would be a problem. I run 3's in 6 Dasher and 284 Win. All is well with heavy bullets and fast twists.

 

[22DASHER]

I have a 3 groove in a 22 dasher, 1 in 8 twist, shooting 75 grn pills. Shoots better than me...

 

[LitLBoy]

Twist in the .22's and the 20 are 1/12 The 6 and 6/5 are 1/8
On a day when I can do my part all these barrels will do .2's for 5 shots
All barrels are Lilja and smithed by Matt Cockrell @ MC Guns plains Montana
LitLBoy

 

[jonbearman]

I have a pac-nor 3 groove 20 cal and it shoots very accurately out to 200 which is my practice distance. Think back in WWII and a lot of the 03 springfields were 2 groove and they shoot accurately for sure.

 

[amlevin]

I have a pac-nor 3 groove 20 cal and it shoots very accurately out to 200 which is my practice distance. Think back in WWII and a lot of the 03 springfields were 2 groove and they shoot accurately for sure.

Yes, those 03's did shoot.

The issue I keep reading about is the land to groove ratio on the smaller calibers. With more land, the theory is that they damage the bullet jacket to the point where it explodes in flight.

From what I'm reading here in this thread is that it's more likely than not a specific bullet/MV problem.

 

[Mega]

Not a .223 cal but did shoot 70gr Berger VLD's in a 3 Groove Pac-Nor 27" 1:8 twist chambered in 22BR. Using Varget it was doing well over 3,000fps but can't find my exact Chrony figures from back in testing days. No problems at all with bullets. Very easy barrel to clean.

Sako S491 .22BR at 150 yards one target here measures a 5 shot group at 0.192" (0.128 MOA). Hasn't been used for some time as I've moved onto a 6.5x47 Lapua for longer range target.

 

[jonbearman]

It may have been just a matter of driving them to fast or bullet jacket design such as the hornady 50 grain SX which means super explosive.Take a 22-250 and drive a bullet at higher than normal pressure and on the box it will say do not drive above 3600fps and some guys ignore manufacturers advice like it doesn't matter.

 

[rminut]

A very popular setup for service rifle is a PacNor 3 groove, 6.5 twist. This is used to specifically shoot 90's all the way out to 1k. Talk to John Holliger at White Oak Armament about it, he has sold them for many years and even made his own chamber reamer specifically for 90's.

I currently have a AR15 in 6br and it happens to have a 3 groove barrel on it. It works so well I bought another 3 groove from PacNor to replace it when the time arrives. The caveat is I shoot NRA highpower, not benchrest, every one has different ideas about accuracy.

The toughest challenge is that 90VLD's are more finicky than other .223 bullets. It's usually not about the barrel but that bullet.

 

[amlevin]

The toughest challenge is that 90VLD's are more finicky than other .223 bullets. It's usually not about the barrel but that bullet.

That seems to be a given. Berger sent me a nice write-up on how to make the "VLD's Shoot".

One thing the write-up did make clear is the fact that you have to think out of the box. Those who are dyed in the wool "jammers", they might have to start "jumping". According to Berger there is a fairly wide "sweet spot" but it varies from "in the lands to .150" or more.". By putting aside ingrained beliefs they say that they can be accurate as any other bullet. The high BC sure makes them attractive for LR shooting. I'm sure that for the "Point Blank" shooters they aren't worth the effort.

 

[cmillard]

my last two barrels that I bought were 3C barrels from Benchmark. although not in .224, they were in .30 and for my .408 chey tac. I love their barrels. clean SUPER easy. when my barrel shoots out on my long range ar-15 (douglas blank by Compass Lake), I will have benchmark do a 3C 1-7"