Light .223 bullets in a 1:7 barrel

[TwoEyedJack]

So I have this new upper from PSA. It is a 20" FN 1:7 twist barrel. I have a bunch of 55 gr. FMJs and tried loads using AA2460, H335, and IMR4198. The results at 100 yards were spectacularly bad, as in 5"+ (10 shots). This using a scope. For comparison, using a 55 gr. Winchester softpoint and H335, it shoots about 1.5" for 10 shots at 100 yards.

I don't normally load with that 55 gr. softpoint any more and am almost out of those loads. I do buy several lighter bullets for other rifles, including a 50 gr. Vmax, a 40 gr. Ballistic Tip, and 52 gr. Sierra BTHP match. What are the odds that one of these lighter bullets will shoot OK with the fast twist?

If one of these don't work, I will just have to keep yet another bullet on the shelf.

 

[rcmodel]

The odds are very good.
Especially with the 50 V-Max and Sierra 52 Match bullet.

55 grain FMJ-BT are the worst bullets made from an accuracy standpoint.

BTW: I often see rifle tests in the Armerican Rifleman magazine and other places of 1-7 AR rifles.

More often then not they will shoot a better average group with at least one light bullet as they will with heavy bullets.

rc

 

[JustAGuy2020]

I have the 16 inch Stainless PSA upper with the 1:8 twist. It shoots the lighter bullets better than the heavier ones. I've had pretty good luck with the 40 gr V-max.

 

[Tinygrouper]

My 1-8 RRR with 24" shoots the 40 gr vmaxes as well as it does the 80 gr SMK's. All near 1/2 moa. You probably need a bit longer bullet for a 1x7 twist.

 

[TwoEyedJack]

I loaded some rounds with Sierra 55 gr. softpoint, Sierra 53 gr. bthp match, Hornday 50 gr. vmax, and Speer 50 gr. softpoint, using AA2460 and IMR4198. Hopefully one will be decent.

 

[NeuseRvrRat]

like rc said, 55 gr FMJBT is not known for excellent accuracy. your problem is probably more related to bullet quality than it is to bullet weight, especially if you're getting decent groups from the 55 gr winchester soft points.

 

[Tinygrouper]

Don't know much about the powders you are using but I've had excellent results with xbr 8208 and the new 53 gr vmax bullets. They are long and very high BC. May do better with your 1x7 twist.

 

[supercalvin56]

I shoot a 7 twist in a 22". It shoots the 40's, 50's, 60's, 70's, and 80's all close to the same. I think the "too fast twist thing" is overblown.

 

[5thSFGroup]

The odds are very good.
Especially with the 50 V-Max and Sierra 52 Match bullet.

55 grain FMJ-BT are the worst bullets made from an accuracy standpoint.

BTW: I often see rifle tests in the Armerican Rifleman magazine and other places of 1-7 AR rifles.

More often then not they will shoot a better average group with at least one light bullet as they will with heavy bullets.

rc

I have to agree, once again, with RC. I did have great luck with the 75 gr Vmax. If you set your scope for a lighter round, the 75's will impact higher...they stay in the barrel longer.

I did luck out. I bought some 55 gr boat tail Hornady rounds a while back and tried them in my 1/7 twist. I got lucky but they were NO WHERE near as accurate as the .75. When I was in Viet Nam, when the M 16 first came out. It was with a 55 gr and it was exptected to tumble..and it did. The rifle was desigend for a 55 gr but the barrel then was...if my feeble memory serves me, a 1/12 twist.....lots slower.

I would not use lighter rounds in the 1/7. The 55 gr, if you are lucky, is the somewhat lightest round, that depending on your particular rifle, may work.

 

[GooseGestapo]

Ditto quality poor on 55gr (or 62gr) FMJ's.

The only other bullets you have to avoid with fast twist barrels are the "Blitz", SX "super explosive", and TNT bullets. These have soft cores and thin jackets and don't even do well in the slow twist .22-250's or .220Swifts.... They are designed for 3,400fps Maximum and that from slow twist barrels such as .222Rem .22PPC's and such. These bullets give better "splat" on varmints from these "classic" elderly cartridges, and benchrest cartridges designed for max accuracy at 200yds maximum.

The 40gr Nosler B.T.s are designed to take upwards of 4,500fps from a 1/12" twist, so are fine in the 1/7" or 1/8" twist barrels. Ditto the V-max and "Blitz-King" bullets.

Just remember that the lighter bullets may shoot flatter to 300yds, but beyond 300yds the heavier 50gr and heavier bullets will actually shoot flatter, buck wind better, and ultimately wear the barrels slower than the lighter weight bullets.

 

[helotaxi]

I have to agree, once again, with RC. I did have great luck with the 75 gr Vmax. If you set your scope for a lighter round, the 75's will impact higher...they stay in the barrel longer.

I did luck out. I bought some 55 gr boat tail Hornady rounds a while back and tried them in my 1/7 twist. I got lucky but they were NO WHERE near as accurate as the .75. When I was in Viet Nam, when the M 16 first came out. It was with a 55 gr and it was exptected to tumble..and it did. The rifle was desigend for a 55 gr but the barrel then was...if my feeble memory serves me, a 1/12 twist.....lots slower.

I would not use lighter rounds in the 1/7. The 55 gr, if you are lucky, is the somewhat lightest round, that depending on your particular rifle, may work.

There is no 75gn VMax. Basing your thoughts on one example of a light round that didn't work as well as the heavier round is misguided at best. Good bullets matter. Good barrels matter. Matching a load to barrel harmonics matters. Twist doesn't. While there's no reason to go out and find 1:7 barrel if you're not shooting long bullets that need that fast a twist, there is likewise no reason to avoid lighter, shorter bullets because you have a faster twist barrel.

 

[P-32]

I’m going to throw a fly in the ointment for a sec. I have a match service rifle which I had designs on shooting 90 gr match bullets out to 1000 yards. When I was researching what twist to get 90 gr. 223 bullets were very new. White Oak Precision had a few barrels in 6 ½ to 1. I had the upper built and shot matches with it using 77 and 80 gr. SMK’s . The thing shot the 77’s very well and the 80’s flew great too. This upper won some matches and won me some money.

When I felt the upper was starting to get some rounds through the tube I ordered anther upper. This time I went with a 7 to 1. I never did develop at 90 gr. Load nor have I shot at a 1000. The new upper became my across the corse rifle and I used the 6 ½ as a loaner gun or used it for reduced matches. I could not bring myself to burn up my 7 to 1 Krieger on a reduced match.

The 6 ½ was still shooting pretty well and it performed well for a buddy of mine who took up the sport but had no rifle. For the reduced matches I use 52 or 53 gr. SMK’s. They work rather well in the 6 ½ and they g=have won matches and money for me. You just can’t convince me the 52’s and 53’s don’t shoot out of this rifle with its 6 ½ twist when I can pull a 196 on a reduced 600 yard target fired at a 100 yards.

If you want 55 gr bullets to work in your AR , Hornaday 55 gr V-Max and Varget in a Winchester case and lit with a Remington 7 1/2 primer will make small groups for you.

 

[Fatelvis]

This time I went with a 7 to 1.

P-32, that sounds more like a screw pitch than a rate of twist!

 

[snakeman]

you need something in the 60-75 range

 

[5thSFGroup]

Helotaxi, here is a copy of the Hornady A-Max. Sorry about the typo on the V Max. This round works great.

Hornady A-Max Bullets 22 Caliber (224 Diameter) 75 Grain Boat Tail Product #: 1165447990 Status: Available 4.8 stars (31) Reviews
$18.99-$101.99

 

[P-32]

P-32, that sounds more like a screw pitch than a rate of twist!

Well, it is a screw twist.........for a bullet.

 

[helotaxi]

Helotaxi, here is a copy of the Hornady A-Max. Sorry about the typo on the V Max. This round works great.

Hornady A-Max Bullets 22 Caliber (224 Diameter) 75 Grain Boat Tail Product #: 1165447990 Status: Available 4.8 stars (31) Reviews
$18.99-$101.99

Intimately familiar with the AMax. Shoot a lot of them in .243 and .308. I use the 75gn HPBT from Hornady in .223. The 75gn AMax doesn't fit in the magazine of an AR.

 

[5thSFGroup]

Fits in my AR just fine and is on target.

 

[Nicky Santoro]

OP,
I've shot both V-Max and Fed Blitz 40 gr just fine out of 1:7.

 

[helotaxi]

Fits in my AR just fine and is on target.

I'm curious as to how since adding the ogive length of the AMax (0.620") to the case length of the .223 (1.750 trim, 1.760 max) yields a COAL of 2.370-2.380". Hornady lists a COAL of 2.390" in their load data. I'd be interested to know what magazines you have that those fit in. The longest magazines that I have only fit a COAL of 2.290" and those mags aren't even made anymore.

 

[nastynatesfish]

i shooot 62-69gr bullets in my ar its a 18'' 1-7 BHW barrel, it shoots them great. ive got a bunch of 50gr vmax and nosler bullets that i load for coyote shooting with them too

 

[TwoEyedJack]

I loaded up some test rounds, using IMR4198 and H335, and several bullets weighing up to 60 gr. and went to the range yesterday. Someone gave me 4+ lb. of 4198, and I am trying to find a use for it. The bullets were 52 gr. Sierra BTHP match, 60 gr. Hornady spire point, 55 gr. Sierra spitzer, 50 gr. Hornady softpoint, and a couple of Tula factory loads. I shot a single 10-shot group of each at 100 yards off a bench. All brass was LC and used Remington BR small rifle primers, and I cleaned the bore after every 20 rounds.

None of the 4198 loads was very good. Maybe my Tikka will like it. None of the 55 or 60 gr. loads was spectacular. In fact, the only one that showed promise used the Sierra 52 gr. BTHP match and H335.

The Tula 62 gr. was bad. However, the Tula 75 gr. HP was pretty good. In fact, it was better than most of the hand loads. One problem, it often failed to cycle the rifle. Several times it drove the bolt far enough back to cock the hammer, but failed to strip a new round off the mag, so you would click on an empty chamber.

Has anyone gotten the 75 gr. Tula stuff to cycle? This upper has less than 200 rounds through it. Maybe it just needs to loosen up? I did spray the bolt with rem oil and it made no difference.

 

[5thSFGroup]

75 amax

When I first looked at these rounds, there was a blurb from an author that stated he was concerned that the round would not fit his mag. The same concern as expressed in this thread. He contacted the mfg and was advised that he could seat the round deeper without problems if he checked for pressure difficulties. He shortened his rounds and did not have any problems. I also called the mfg and was advised the same. I seated my loads to shorten them in order to fit the mag in my AR. This worked great for my AR. As has been discussed. over again, each weapon is different. This worked for me and for the individual I relied upon.

I have a very tight 1/7 barrel and it loved the roundl

 

[helotaxi]

Can you post a pic of some of your loaded rounds? Other than the obvious problem of the ogive beginning inside the case neck, I'd be concerned about neck tension, especially with an AR. The .223 already has a very short neck. Leaving less than half of its length to grip the bullet would give me pause.