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Can someone share their experience shooting a 77gr bullet (.223 Rem) with a 1:9 twist barrel?
Are you achieving .75moa groups?
What velocity are you shooting at?
I would like to re-chamber my .223 Rem to an Ackley Improved. Who would you use to do it if it were you having it done?
Sierra sent me some samples. They shot very well in my factory 1-9, .50moa. Don't have chrony, sat them on some H4895 just to see what they would do. Pricey though in my opinion, can't afford to shoot them all day long.
IMHO, 77 GR is just a bit on the heavy side for a 9" twist. I just sent 2, 223 barrels to Sinman this morning to the chamber Ackley Improved. Bill
Its not the weight, its the length, not all bullets of the same weight are the same length. Also it depends on how fast you shove them out the snout. Faster is better for .224 bullets in almost every case.
I have a 1:9 20" bull barrel AR-15 that shoots same hole 3 shot groups at 100 yds using 24.5 gr of RL-15 with Nosler 77 gr bullets and no pressure signs. It is the same load I use in my Service Rifle in competition. But they are too long for the magazine so you have to load them one at a time in an AR-15.
I would think that a bolt action would be able to do the same.
Lilja's site has a chart thats down the page a bit... Bill http://www.riflebarrels.com/products...wist_rates.htm
I have a 223 ( Shilen) 26 inch, varmint countour, 1:9 twist.
,
I know you said, 77gr.,
I have not tried the 77gr., but did try the Hornady 75 gr. A-Max.
my "Chrony" gave me this results.
Varget, 5 shots, average, 2925fps
H-4895, 9 shots , average, 3029
I have 50 of Sierra 69's loaded, but to much snow to try to shoot them yet.
with the Varget, & the H-4895 , I'm using the same powder charge.
I have found this difference with the 50 gr. V-Max's too. H-4895 with the same charge as Varget, approx. 100fps more.
at 100 yds., pretty consistant, 3 shot gr. for the H-4895 will be in the .3's, 5 shot group, in the .4's to 5's
the varget, pretty consistant, 3 shot, in the 2's, on occasion's all touching, 5 shot group, in the 3's
probably a better shooter may improve on these.
Im aware of the length issue its just easier to reference the longer bullet by weight than by length. I have shot many 77 MK's in my White Oak AR as well as 69's, and 75 Hornady.Quote:
Originally Posted by hotbrass
I have a BVSS 1:9 arriving tomorrow and have 69's 75's (moly) and 77's HPBT and will load each. I do know that at 600yds my 1:9 AR wouldn't do it as well as the 1:7. but its not a 26" barrel.
If the 77gr SMK's HPBT can hold its own in a 26" 1:9 then the plan will be to re-chamber to AI and shoot it, if not then I'll replace the barrel with a 1:6.5 in AI and shoot 80's.
The best way to answer the question is to load some up and give it a try.
Fatdaddy what twist barrel did you re-chamber the AI's? Did you say 2K barrels? Why? Just curious. Who does the work for you?
TnTom
I sent (2) standard 223 Remington barrels to Devin Sinner. He is Sinman on the forum. He is a gunsmith , Sin Arms ,web site is sin-arms.com. They are both 1-9 twist, savage, stainless steel, and hes going to re-chamber them to Ackley Improved. I live in Kansas, so I mailed them to him in SD.
1 of these barrels loves 75 gr amax, one ragged hole. The other not so much... I plan on working them hard with 40 gr vmax on the pdogs this year. Like you said, when it comes down to it, you got to load it up and see what it likes. Bill
Got it. Ya think I could have figured out that no one sends 2,223 barrels out for re-chambering. duhhhhhhh. Thanks for clearing that up. I'll check out the Sin-arms. Thanks again.Quote:
Originally Posted by fatdaddy