Weird grouping issue

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Grouse870
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Weird grouping issue

Post by Grouse870 » Fri Oct 12, 2018 2:05 am

I’m having an issue that I’m kinda unsure what it could be. My first shot is high left next two are right where there supposed to be. It’s consistent with Barnes factory 110 blacktips. It’s a known scope leupold 2x7 in a adm scout. The upper is a palmetto built upper 16” barrel 1x8 twist pistol gas. I tried with the first load on the right hand side and the left hand side I tried different ammo and it would still put the first round high (sometimes just high but usually high left). I tried off an actual rest and I tried off of bags. Nothing the only thing I didn’t try was a different mag (magpul 10 round). Everything is tight nothing is loose. Any ideas? I had hopes of taking this deer hunting this year but I had to shelve this gun until I can figure this out. After deer season I’ll put the scope back on and maybe pick up some different ammo but I’d like to see if there’s something I’m not thinking about.

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smustian
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Re: Weird grouping issue

Post by smustian » Fri Oct 12, 2018 2:56 am

Do you clean the barrel after every range trip? If so, make sure you wipe the barrel completely dry of oil before shooting. Residual oil in the barrel can throw the first shot. Or after your next range trip, do not clean the barrel. Some barrels shoot better when they are dirty. Just clean/wipe down the bcg. Clean the barrel after the season is over.

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Bob the nailer
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Re: Weird grouping issue

Post by Bob the nailer » Fri Oct 12, 2018 6:45 am

Clean your barrel as you normally do after the last dry patch apply a wet patch of Loc-ease
https://www.truevalue.com/3-4-oz-graphi ... id=gooshop

Then clean the chamber of any lock-ease. Your first cold bore shot will be inside your normal grouping, been working great for all my bench and varmint rifles.
One ragged hole! The quest for accuracy continues...

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Bob the nailer
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Re: Weird grouping issue

Post by Bob the nailer » Fri Oct 12, 2018 6:52 am

One ragged hole! The quest for accuracy continues...

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Grouse870
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Re: Weird grouping issue

Post by Grouse870 » Fri Oct 12, 2018 11:58 am

Sorry I guess I didn’t explain it very well. The first shot would go Wild I’d shoot 2 more then go check the target. I would put 3 more rounds or so in the gun and fire again. First shot high left next 2 we’re fine. It’s every first shot out of a magazine. Doesn’t seem to matter if I close with the bolt release or pull the charging handle back. First shot out of the mag regardless of side of the mag goes wild.

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bangbangping
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Re: Weird grouping issue

Post by bangbangping » Fri Oct 12, 2018 2:38 pm

Lots of questions:
1. New barrel?
2. Only black tips or other bullets, too?
3. Tried a different magazine?
4. Have you ejected the first round without shooting to look for tip damage?
5. Have you ejected a subsequent round to examine?
6. Have you tried hand feeding the first round?

Grouse870
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Re: Weird grouping issue

Post by Grouse870 » Fri Oct 12, 2018 2:47 pm

Yes.
Yes. (Still shoots high)
No.
Yes. Didn’t notice anything
No.
No.
I checked the feed ramps and everything looks good and smooth there. I’m going to try hand feeding a round and using the forward assist to seat the round as well as trying maybe a 300 specific mag. But I’m still not sure what could be causing this issue

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Re: Weird grouping issue

Post by rjacobs » Fri Oct 12, 2018 2:54 pm

How long are you waiting between strings of fire?

It sounds a little like cold bore, BUT I cant see your barrel cooling that much between strings unless it takes you 30 minutes or an hour to walk down range to check your target and walk back.


IF its repeatable, just compensate for it on your 1st round only. If the first round is ALWAYS, for whatever reason, 2" high(or whatever it is), just compensate for that like it was your cold bore shot(which likely when you are out hunting it WILL be a true cold bore shot).

Cold bore shots are almost always off of zero, but they also are almost ALWAYS in the same place so its easy to compensate for them.

Grouse870
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Re: Weird grouping issue

Post by Grouse870 » Fri Oct 12, 2018 3:08 pm

I get what your saying but it’s not consistently in the same spot it always high left but some time it to the left more or sometimes higher. It’s also with the barrel warm or cold. So if it is the barrel then I’m pulling the barrel I’m not going to put up with that. None of my other AR or rifles have a cold bore shot that far off. I’m hoping it’s not the barrel but kind of at a loss as to what it could be though

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Re: Weird grouping issue

Post by rebel » Fri Oct 12, 2018 3:59 pm

Is your barrel free floated?
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