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RWBlue
04-29-2008, 02:38 PM
I am having issues getting my AR Whisper to group. The groups are generally horizontal. They are 3-4 inches at 100 yards.

I am shooting a barrel with a good twist and good manufacturer. JP adjustable gas port. I am shooting off the bench (not something I do on a regular basis).

I have tried this with Reeds ammo and my reloads loads (most of the brass is first time through the gun). The chronograph data tells me that the load is fairly consistent (mine and Reeds).

It could be me. I am not a bench rest shooter, but I am doing better with my other rifles.

It could be the attachment of the suppressor. I am using a Gemtech QD.

What is considered a good group for a semi-auto AR Whisper? Am I asking too much from this gun?

pug
04-29-2008, 07:36 PM
The guns are capable of sub 1/4" groups but that doesn't mean you will get it. Generally for horizontal stringing I try to determine if it is from heat first. Walking due to heat generally causes the first point of impact to be close to on target. The second one is off to the side a fair amount the third is off even further but not as far off from second to third as was first to second. So on with the fourth and it usually settles in by the 5th shot. The group size of six - ten give a pretty good indication of what it will shoot. This isn't an exact description but one sure sign of heat is when you let it fully cool it does the exact same thing again and then again. Could be a barrel extension to receiver alignment causing some movement too. Check the crown of the barrel to make sure no dings there it will cause them to throw off. Make sure barrel nut is tight. If using optics you will want to try at least one other to make sure it isn't moving due to recoil. Hope you figure it out.

RWBlue
04-30-2008, 05:46 PM
Could be a barrel extension to receiver alignment causing some movement too. Check the crown of the barrel to make sure no dings there it will cause them to throw off. Make sure barrel nut is tight. If using optics you will want to try at least one other to make sure it isn't moving due to recoil.

I am using a YHM free float tube. So I don’t think the barrel could be loose?

How do you check the crown?

Good idea on the optics and heat.

Artful gave me some ideas on another forum.
He said let someone else shoot it.
Shoot without suppressor
Try other bullet weights

jarhead1086
05-01-2008, 01:44 AM
I check my crown by sticking a clean Q-tip in about a 1/2" to reflect some light back out and look with an eye loupe for burrs or dings. This is how I look for copper deposits too. Removing the suppressor and trying another scope would be my first bets like Pug and Artful said. I had a weld break on a .223 can which tweaked the groups in a mostly horizontal spread, hopefully its the scope. If it is the can/mount be glad you have a Gemtech, they will take good care of you. My weld broke because of abuse by another shooter, I don't share my NFA anymore. The newest Gemtech G5 mount is mostly titanium and is very nice.