Gunsmithing Huge groups: help with mostly Volquartsen parts build

[required_user_name]

I am getting huge groups out of my quasi-1022. You'll be below by what I mean by quasi, but the groups are about 2 feet wide at 25 yards. This happens with several different types of ammo. They're all the same. It's all subsonic, haven't tried supers. The paper shows that some bullets are tumbling, so I think it's the barrel and receiver rather than stock and optic. The optic is on solid and there's no wiggle.

I made my own Summit rifle in a sense. I bought a Volquartsen carbon fiber barrel, trigger and straight pull receiver. I assembled it myself, added the Boyd's AT-One stock, a Leupold rimfire scope.

Thoughts? I'm wondering if I need to fiddle with the number of shims between the barrel and receiver. That's all I got.

 

[FisherT&C]

If there is not a loose barrel issue. Check for muzzle brake strikes, if you have a brake. If that is not the issue there may be a reverse taper at the muzzle, essentially the muzzle has a wide mouth. The only way to check it is with gauge pins or bushings. Hope that helps.

 

[Adam B]

I had 2 of their carbon fiber barrels and they both shot terrible. I sold them and bought a Kidd barrel and now the gun is a tack driver.

 

[RTH1800]

Only a bad barrel or break strike can make a bullet tumble.
You can never go wrong with a KIDD.

 

[required_user_name]

Thanks guys. I ran it with and without a SiCo suppressor. No brake. Same bad groups either way. Barrel doesn't seem visibly loose. I can't wobble it.

Might the headspace be off? Here are several pictures looking up the magwell. I took the picture from an angle so you could see the barrel sticking into the receiver and another dead on from the top to see the protrusion. It's with and without the bolt closed. Not sure if any of that looks off to you.

I have go and no go gauges. I'm familiar with how to use them on an AR, but not with this. Any tips there would be appreciated too.

Worst case, I'll just pick up a Kidd barrel.

 

[required_user_name]

I had 2 of their carbon fiber barrels and they both shot terrible. I sold them and bought a Kidd barrel and now the gun is a tack driver.

Any shims to fiddle with between the barrel and receiver?

 

[RTH1800]

Keyholing is a barrel issue. Unlikely to fix it.

 

[GH41]

Did they forget to pull a button through it? Sounds to me like it isn't rifled or the bore is way over sized.

 

[required_user_name]

Did they forget to pull a button through it? Sounds to me like it isn't rifled or the bore is way over sized.

Excellent question. I had not looked before, but yes, I see the rifling.

 

[OG10]

Have you contacted Volquartsen ? If everything checks out on your end I would give them a call. P S I had a pic base come loose one time opened the groups up to 2 inches at 50 yards, but not keyholing, the point is I believe your barrel is probably the culprit.The key holing is a by product of stability, if your bullet is not being stabilized by the barrel it will do funny things.Hope this helps where are you located and do you have a borescope?