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Greetings! Looking for some help and direction to some information possibly. I recently purchased a 6ARC (16” gas gun) and later found out the barrel is a 1:8 twist! Everything I’ve seen is 7 or 7.5 never seen 1:8 anywhere before! Shoots 90gr eldm’s great no problem there. But I want to take Midwest whitetail/mule deer with it. Can I do a heavier bullet?
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Howdy Arc'd! Welcome to the forum. 1-8 twist should work with bullets up to 105gr according to a brief search I made for 6mm bullets in barrels with a 1-8 twist. Like you, I thought 6ARC barrels came with either 1-7 or 1-7.5 twists. Who made the barrel in your rifle? I have both gas & bolt 6ARC rifles with 1-7.5 twist.
The trick is growing up without growing old. -- Casey Stengal
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Thank you! I suppose that’s the lightest I would go on a big deer around here. Uncertain of manufacturer, can’t find a name on it. It is stamped “6mmARC 1:8” right behind the barrel tho, not sure how I missed it.
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Was the rifle you bought already a complete rifle or some type of kit? If complete, who built it? It may give me a clue who made the barrel. Off the top of my head Bear Creek Arsenal, I know for sure, makes 6 ARC ARs that have 1-8 twist barrels.
The trick is growing up without growing old. -- Casey Stengal
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It was an upper a local guy built and needed some quick cash and in my head thought it would be a steal. I can’t say it wasn’t a good buy because it’s accurate cycles well and will most likely be a great coyote gun. However I grew up with the ol trusty .270 as a deer killer and I’m just not sold on this being the same. I got some 103gr Hornady hunters today hopefully group it this weekend. Also, Hornady website says 1:8 recommend for their 6arc rounds?
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(10-29-2024, 02:50 AM)Arc’d Wrote: It was an upper a local guy built and needed some quick cash and in my head thought it would be a steal. I can’t say it wasn’t a good buy because it’s accurate cycles well and will most likely be a great coyote gun. However I grew up with the ol trusty .270 as a deer killer and I’m just not sold on this being the same. I got some 103gr Hornady hunters today hopefully group it this weekend. Also, Hornady website says 1:8 recommend for their 6arc rounds?
Website say 1-8 for 103 and above doesn't list for the 80vldt, Hornady reloading says 1-7.5 and it is not the same as a 270 but does a very good job out to 300 for me . Mine is a bolt gun 24" barrel
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11-13-2024, 03:20 PM
(This post was last modified: 11-13-2024, 03:21 PM by Rickhem.)
One of the standards for the 6mmBR and heavier bullets is the 8 twist barrel. I know my 6mmBR with a 8 twist barrel shoots the Sierra 107MK bullets quite well at distance, but that is a 26" barrel. My 6ARC is a Howa with a 20 inch, 7.5 twist, and shoots those same 107MK bullets, and some older 105AMAX bullets (which are even longer) without issue. The 7 and the 7.5 twist lets you shoot heavier bullets at a little lower velocity, which often happens in shorter barrels like yours, but that doesn't mean they won't work in an 8 twist. Most .243 Win factory chambered rifles have barrels that are 10 twist, and they'll shoot hunting bullets up to 100 grains just fine.
Most of the long range target bullets are the long heavy ones, and most of the better proven hunting bullets are in the 80 too 100 grain range. With that in mind, I don't think you will have any problem hunting with your rifle. There are some other variables at play, but in general, you'll have to try it yourself and see, and that's half the fun.
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Thanks for the info guys, not sure how to post pictures in here but the 80gr ELD-VT’s I get groups I can cover with a penny at 100yds. However the 103gr hunters (both Hornady factory loads) opens up to roughly 1moa groups. Got just a few days left of deer rifle season here with not much moving it might be testing on some coyotes. Also, I found a 18” 1-7.5 twist barrel on sale would it be worth the switch?