1:7 vs. 1:9 on 10.5" barrel

[jstevens]

After I asked about it, what I was told was "the impacts on the target looked like a line, and not the normal circle hole." The impacts on the berm where a lot closer to the guys pulling the targets in the pit. Just to make sure I am clear.... I have not seen this in person, but my father claims to have been at the range when it happened. I am going to trust him on this one..

 

[jstevens]

And wasn't this thread supposed to be about SBR's?

 

[KurtM]

No this was about twist rate.

then someone came on and said 1X7 would spin the jacket off a 55gr. bullet and lots of "other" B.S. As for what your father saw it can only be chalked up to someones WAY underpowered reloads, which can be done with any weight bullet BTW. When I use the Hi-Power range by myself..."so no one can be in danger" I routinely shoot my AR at 600 with G.I. Ball ammo or equivalent reload. It delivers nice ROUND holes, it IS a bit wind sensitive, and it impacts the berm in the EXACT same place as My 77 grain loads according to My spotter in the pits...who didn't feel in the least threatened by the 55gr bullets, nor I his. After ACTUALLY testing this "Range Myth", I can definitely say...BUSTED!,...But I know this guy whose brother in law saw another guy who claimed that his cousin.....and on and on and on.

As for twist in any barrel go with the fastest twist you need to stablize the heaviest bullet you want to shoot, for Sub Sonic in a short barrel definitely go with the 1X7" KurtM

 

[NikatKimber]

I picked up some 69gr .223 bullets in part of another deal, and was wondering if it would be worth trying them in my AR, which is a 16" 1x9 twist?

 

[KurtM]

Yes 1X9" likes the 69 gr. bullets in general, only 75s and 77 are iffy in a 1X9"

 

[idleclamp]

I picked up some 69gr .223 bullets in part of another deal, and was wondering if it would be worth trying them in my AR, which is a 16" 1x9 twist?

When I get home from this trip, I plan on reloading some 69gr. for my 20" varmint with 1:8.

Just to set the record straight, this thread was about twist rate on a SBR. So you're both wrong...er....I mean right....uh....well, that's what it started as anyway.

 

[jstevens]

kurtm I do agree with you. as you probably know most guys on the high power range reload, and more than likely it was due to some one using a real light load. Never the less they don't allow the use of 55's, or any thing under 69. I use 55 grain my self and I have never had a problem with them with my "SBR" with a 1/7 as mentioned above, but not on the 600 because I choose to follow the range rules. If you choose not too that is on you and " hope you don't get caught." we as a society have rules, laws, to sometimes protect our selves, well from our selves. far to often do i see people fail to follow the rules, laws, and they die or injure their self. I see it every day on the job. Now as far as "I know this guy whose brother in law saw another guy who claimed that his cousin.....and on and on and on." I have only one father who I trust with my life, and if he said it happened, It happened. I don't Know what kind of relationship you have with yours, but mine is very well. I'm not trying to rip on you so please don't take this post as one. Oh and this thread was about the twist rate on SBR's

 

[KurtM]

"They" don't "allow" anything less than a 55gr DURRING a sanctioned match, by their own choice. NO WHERE in the club rules will you find that little tidbit, NOR is it posted ANYWHERE on the High Power range. I was also told this little thing by one of the Hi-power gurus and that it was true for ALL Hi-Power ranges in the U.S....A quick call to the C.M.P. and several Clubs that run Hi-Power, such as the N.R.A. Whittington Center, and NO ONE had ever heard of it, and besides when the Army and Marine reserve units us the range and the pits, they all use 55gr and 62gr ammo, and no-one from Hi-Power says a word, so what we have is an informal "rule" with absolutely NO backing.

I was not doubting your father. I was pointing out how these rummors get to be "The Rule", sorry it came across that way.

Here is another real "rule" on one of the 1000 yard ranges I shoot at. NO Flat based bullets allowed because they key hole at 1000 yds. This is absolute B.S. but someone knew a guy, who saw a girl whose son knew a Rabbi, who told a rimfire shooter that he saw it all from the 1000yd line while he was sigting in his .36 calibe squirle rifle....see what I mean? Kind of like Glocks can pass right through a metal detector...everyone "KNOWS" thats true! KurtM

 

[jstevens]

Sweet I will have to try the glock thing.

 

[NikatKimber]

I picked up some 69gr .223 bullets in part of another deal, and was wondering if it would be worth trying them in my AR, which is a 16" 1x9 twist?

Yes 1X9" likes the 69 gr. bullets in general, only 75s and 77 are iffy in a 1X9"

Well, just checked, I thought the bullets were 69gr and a handful of 75gr, but not so, they are 75 and some 80gr bullets. Is it even worth my time to try the 75s in the 1x9 or just sell them and get lighter bullets? I have an unopened box of 250 Sierra 75 grain .223 bullets, and an opened box with maybe 75 or so more of the 75gr, and then 100+ of the 80 gr .223. Can't remember the make on the 80 gr bullets right now.