YO HOOT! Well Crap. Half Crap Anyway.
The handi rifle project is not a complete success, but not a complete failure either.
I started the sight in from 25 yards to get it on the paper, suppressored up.
Didn't work. First time ever I couldn't get one on at 25 yards.
Moved to 10 yards and it wasn't on a 12 inch sheet of paper I cut out of a feed sack. So I just picked a place low on the white target backing (it originally was a plastic political sign. A friend picks up the big ones the day after the elections and cuts them to fit the target boards he makes). Let one fly. High right and kind of oblong. Slung another one that way. Generally in the same area and full keyhole. FROM 10 YARDS. CHINGA DINGA!
Took off the suppressor and it started behaving itself. Moved back to 50 and got it on. Moved back to my 100 yard mark and fired one at the gong. It hit exactly where I was holding on the gong.
So, no suppressor for now until I figure it out. No signs of bullet strikes any where on or in the suppressor, that I can see. So now it's an itty bitty rifle that will pack great that hits where it's pointed, only it's not as quiet as I had hoped.
Answer to the first question. Remington factory 140's from Academy.
My money is on off-axis threads and shoulder.
A slight baffle kiss is enough to deflect yet is hard to see. Even if it is just VERY CLOSE to hitting, it can deflect. But if it is keyholing... bad juju.
Do you know how they threaded the barrel? Hopefully they indicated off the bore and used a single point tool in a lathe. Also, the shoulder should be perpendicular to the bore as that is how most cans index. Threads are important, but the shoulder is paramount.
John I know they used a lathe.
And they had the suppressor to use to thread match. Bunch of stuff that you would understand but I didn't. I'll go back and ask next week. The guy is not new to threading for suppressors. I will certainly ask him about it though.
Try this - with the barrel off, thread the can on and
peer down the bore at a light. The eye's ability to center will usually show up a mis-alignment.
Sounds like they knew what they were about. My initial worry was someone just attacked it with a die and it is almost impossible to end up with proper alignment that way. Still, some indicate off the exterior of the barrel instead of the bore and sometimes the bore isn't aligned with the exterior...
Try this - with the barrel off, thread the can on and
by Slow Hand 
, Indiana, Saturday, July 20, 2013, 23:45 (4148 days ago) @ John K.
Yep, I always look down the bore, even for a trusted machinist. You're shooting a 7mm bullet through a .30 cal can, right? That should give you even more 'wiggle' room. Speaking of wiggles, you might try shooting a couple shots at a new target up close, like 10-15 feet without the can. You may have some stabilization issues with that short barrel. I know little about the 7-08 but if a lighter bullet is available, try that and see what happens. I know that some various subsonic loads don't stabilize at the muzzle, but settle down pretty quick, and you can get baffle strikes. If you see an oblong hole at very close ranges and round holes further out, that could be your issue.
Tried that. At 10 yards it makes round holes.
I thought about the short barrel thing, but it shoots fine without the can. Can shoots good on the two 30 cal's I've used it on. It's a marriage problem. Not and individual problem. I'm going to pursue it, but in the mean time, I'll just stick plugs in my ears when I shoot it. Although it wasn't as ear splitting as I was expecting without the can.
Tried that. At 10 yards it makes round holes.
by Slow Hand , Indiana, Sunday, July 21, 2013, 11:01 (4148 days ago) @ MR
Might try it closer. Some bullets 'self stabilize' pretty quick. I've always read to try it at 5-10 feet. Longer skinnier bullets take a faster twist rate but also can self stabilize faster than a short stubby one. I've shot up to 235gr .30 cal bullets at subsonic speeds through both .308 and .300 blk rifles with no troubles, but I have head of folks having. issues.
Yep. Just because they use the right methodology doesn't
by Hobie , Shenandoah Valley of Virginia, Sunday, July 21, 2013, 12:20 (4148 days ago) @ John K.
mean they do it well.
--
Sincerely,
Hobie
I know Hobie. He's done every thing else I've had done
in an exemplary manner. And he's not new at this. Dave Gregor did it. See below>
I hope that it is an easy fix. I suppose we are
by Hobie , Shenandoah Valley of Virginia, Sunday, July 21, 2013, 18:46 (4148 days ago) @ MR
presuming that the can isn't wrong in that area.
--
Sincerely,
Hobie
Sorry to hear of your "challenge" Mark.
by Hoot , Diversityville, Liberal-sota, Tuesday, July 23, 2013, 21:01 (4145 days ago) @ MR
Keeps it interesting, don't it? 
Either way, I think a 16+" 7-08 ought to be right handy, quiet or not. I recently picked up a Ruger American in that caliber. It's a very 'polite' cartridge so far.