40gr bullets shooting well in a 1-7 twist?

[Another_Kelley]

I'd love to hear from any of you having success with any light-weight .224 diameter bullets (40gr or less) - shooting well in a 1-7 twist barrel... and I guess I would vaguely define that as; not blowing up en route to target & 1moa or better.

I'd like to try and do some varminting this season with a 20'' 1-7 AR of mine, but the majority of my .224 bullets are pretty light, and really more ideal for a 22-250. If you've had success shooting any 40gr or lighter bullets -accurately- through a 1-7 barrel, I'd really like to hear the load details & rifle/platform you experienced it with.

Thanks for the input.

 

[Rule3]

This may not help much but it depends on the actual bullet and brand.

Some time ago I contacted Sierra (I think) on a similar situation. I apologize that I can not find the information,

Anyway, I had some lighter bullets like 45 grains and asked the same question as I had them for a 1:14 twist bolt rifle that I sold, I wanted to use them up. The tech told me that the bullet in question had been designed for the 22-250 so it would hold up on the faster twist of my AR (1:9)

Again this was several years and I can not recall the details but it really depends on what exact bullet, If it is another brand I would contact the maker, I have cleaned out my e mails so no longer have the info,

So it is a somewhat probably, sort of maybe.

 

[Reloadron]

I never had much luck with the 1:7 barrels and the light 55 grain bullets. While they shooy great in my 1:12 bolt gun I could never get really tight groups in any of my four 1:7 twist AR rifles and that includes a few brands/designs. Some guys claim great success but I never had the best of luck. I tried Hornady #2249 BTHP Match, Nosler Ballistic Tip 55 grain (had one load of those keyholing in two rifles at 100 yards) and finally Sierra 53 grain HP Match #1355. Maybe I didn't try enough loads but I like the 69 grain and heavier in my 1:7 twist guns. I finally quit wasting bullets.

Again, some have claimed no problem with the light bullets (55 grain and below) in 1:7 twist but never did work well for me.

Ron

 

[mantawolf]

I was not able to pattern with 55gr bullets in mine, went with 77gr hpbt instead. Sorry I am not help with the 55gr either

 

[Rule3]

The OP is asking about 40 grains or less.

 

[JimKirk]

My Son has a SIG M400 AR with a 1/7" barrel and so far we have not been able to find a bullet/powder combo that will shoot very well at at with 50 gr VMax & 55 gr Vmax bullets ... it shoots the 65 gr to 69gr bullets fairly good ...

Just my opinion ... everybody has one ... the 1/7" is too fast twist for bullets less than 60 grains .... barrel makers would have been better off with a 1/8" or 1/9" and left the 1/7" to those folks who have to shoot the "heavy" bullets for the .223/5.56... YMMV

 

[GooseGestapo]

IMO, it's more than just the twist.
SAAMI spec chamber .223's have a much shorter throat than either .223 Wylde or 5.56 NATO spec chambers. The short 40gr and lighter bullets aren't going to shoot as well from the longer throats irregardless of twist rate. Most 1/7or 1/8 twist barrels have either the mil spec or Wylde throat.

The Nosler Ballistic Tips are rated for over 4,000fps. If they won't shoot to expectations, most likely nothing in that weight range will.

 

[Hacker15E]

Rather than going with the wives tales, here's a thread with some actual empirical data on 40/52/55 grain going out of a 1/7 twist barrel:

http://www.m4carbine.net/showthread...Fired-From-AR-15s-with-1-7-quot-Twist-Barrels