I just put a 17 inch GM barrel on my 10/22.  Did the manufacturer suggested break in procedure.  Trying to sight in and find an ammo it likes.  At 25 yards Federal hv match will shoot 5 round touching, CCI mini mag and Federal automatch will do almost as well, and several varieties of bulk pack would do just fine for hunting.

Moving to 50 from a concrete bench, bags front and rear, things fall apart.  The only ammo to consistently hold under an inch is the hv match.  All the rest group over an inch to an inch and a half.  The CCI will put 3 or 4 into a super tight group, then throw a round or 2 out a full inch.

The barrel shank was tight in the receiver.  Face of the bolt was polished but not dimensionally changed.  I'm using a Hogue nylon stock.  On install the barreled receiver rocked in the stock at the action screw as the barrel is free floated.  I built up an epoxy pad approximately 2 1/2 inches in front of the receiver, so now the stock supports the barrel receiver at the rear, the takedown screw, and the pad under the rear of the barrel.  After initial groups, the action screw was loosened to "just snug" and that definitely improved things.

Did I screw up by putting a support pad under the rear of the barrel, are my expectations for this barrel too high, or do you have any other suggestions?

Never had a issue with GM barrels, pad may be a issue. Have a extra stock to try? I would do that and go from there.

No extra stock, but I can sand or grind out the pad.  It's not visible when the gun is assembled.  I may try that at some point, thanks.

All I can tell you is Hogue stocks are good field stocks but not known for their accuracy potential and neither are CCI mini mag's or Federal Automatch. Both decent, reliable rounds but not super accurate unless you get lucky and your gun happens to love them?

The first thing I'd try is some better ammo like Wolf Match Target\SK Standard Plus (Same ammo different box) or even Wolf Match Extra\SK Rifle Extra. If better ammo doesn't help, looking at the bedding or a different stock may be the next step?

Amen to what airgunner said! Get better ammo, just about anything will group at 25yds. better bullets are required any farther unless you stepped into a freak rifle or lot no. of ammo.

1200fps or slower usually will do better, even standard vel. CCI is not bad, some are doing well with the Eley force in HV.

All my 10/22s like a pressure pad but 1, with a nylon stock it will be hard to tune too flexable.

That said sounds like your close.

Thanks for the suggestions, as luck would have it Mills Fleet Farm had Eley match and club on the shelf today. I grabbed a box of each to try this weekend.  They also had an Eley hv hollowpoint, but I passed on that.  The hollow point was over 12 bucks for 50, match was the cheapest at 9 bucks.  Doesn't that seem backwards?

I'll keep an eye out for a good price on Wolf.

Correction, it was Eley Target and Club.  Both shot one hole at 25 yards and 5 shot groups under half an inch at 50.  Problem solved, I know what the barrel is capable of now.  With lesser barrels I never realized how inconsistent average .22 ammo could be.

I'll be looking into some other premium ammo just out of curiosity now.