Gunsmithing Bedding question...not how to, but

[eddybo]

what am I doing wrong??
I have been having great results from most of the guns I have been bedding out of the 20 or 30 I have done I have 4 or 5 that stick in my mind as not being quite right. All of the "bad" bedding jobs I did were on aluminum bedding block stocks. They either had a touch of fore end stock movement or I ended up having to shim the tang with .005 non-compressible shim stock. Some shot great some needed the shim in order to group well.

I have read every tutorial I can find. I have watched Don Geraci bed a whole bunch of them, and gotten tips and critiques on my methods.

Here is the only thing I can think of that could cause any stress....the tape around the headless screws (which is not tight by the way) could be binding just a bit when I squish the action down into the devcon. Is that possible?

The reason I am wondering is I have just been tinkering with a gun for two afternoons trying to find the cause of consistent flyers. It was shooting tiny little two or three shot groups then spitting a shot to the right and up 3/4 inch or a bit more.

The bedding felt perfect when I loosened the screws no movement whatsoever. So I considered and everything I could think of including changing the firing pin spring and scoping the chamber even though it indicated very well after I chambered it. Finally we decided it had to be bedding. I shimmed it (well actually Don shimmed it) and it settled down immediately.

Could that tiny amount of pressure exerted by tape around the screws cause the problem? Any ideas that could help out?

 

[Al Nyhus]

Re: Bedding question...not how to, but

If you're taping around the headless screws for your clearance, here's another approach to eliminate a problem there. I drill the action screw holes to 5/16" (.312) and then epoxy these flanged Delrin sleeves into the holes....their o.d. is .312 and the i.d. is .250. I make my headless action screws .244-.245 o.d. and they fit perfectly inside the sleeves. When the bedding is cured and I remove the barrelled action, I either tap the sleeves out or back them out with a drill bit and clean up the holes. The result is the action is perfectly centered over the holes with .030-ish clearance around the action screws.

I lap all these bedding blocks with a lapping bar (similar to a scope lapping bar) and open them up enough so I can get at least .030 of bedding thickness between them and the action. Most of these blocks are in there pretty screwed up and lapping them lets me center the action w/o stressing anything. The old wives tale of 'skim bedding' these blocks just doesn't cut it.

For what it's worth.

 

[gamma]

Re: Bedding question...not how to, but

would it not be a nightmare trying to get these flanges back out. Obviously not but how do you get them out if they are epoxied in.

 

[eddybo]

Re: Bedding question...not how to, but

I love those sleeves....and I have delrin....great another project.

I got a couple of calls from some of the very knowledgeable members here that helped me out a bunch. I think I have figured out what I was doing wrong. I have one I need to do tomorrow so I will see if the great advice works.

 

[Nocalphoenix]

Re: Bedding question...not how to, but

Eddy, how about sharing the possible wrong methods in case it is something Im already doing as well.

I know I switched to Roscoes method taping the barrel in two spots and letting the action float completly on the last three jobs and have been extremely pleased with the results. No movment on the indicators and no wild fliers on paper. Im grinding out an erratic lightweight right now to redo the bedding with the above method to see if the results change. Previously I would wrap the barrel in one spot for clearance and centering in the stock and then sucking the action down with surgial tubing. I was pretty satisfied with results but would occassionally have fliers I could not explain. We will see shortly if the bedding was the cause of the fliers or if it was the loose nut behind the trigger.

 

[eddieharren]

Re: Bedding question...not how to, but

If Don can't show you what is wrong and, how to fix it, then no one can.

 

[wnroscoe]

Re: Bedding question...not how to, but

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Norcal Phoenix</div><div class="ubbcode-body"> I know I switched to Roscoes method taping the barrel in two spots and letting the action float completly on the last three jobs and have been extremely pleased with the results. No movment on the indicators and no wild fliers on paper. </div></div>

I've been doing stock work (20+ years) longer than I've been building rifles. The method I now use has worked flawlessly for me everytime. It's the method I posted.

 

[eddybo]

Re: Bedding question...not how to, but

Your right Don knows about as much about bedding as anyone, and he has been very kind to show me his methods many times...I am kinda slow I guess....but he does not bed aluminum bedding block stocks, he scrapes them, or on a quick fix shims them with non compressable shim stock.
I have tried the scrapeing with some sucess but do not have his talent at it, or maybe his persistance I am lacking.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DocEd</div><div class="ubbcode-body">If Don can't show you what is wrong and, how to fix it, then no one can. </div></div>

 

[eddybo]

Re: Bedding question...not how to, but

Norcal pheonix....if you are doing as per your post and WMRoscoes instructions you are good. I was deviating from his process in some minor ways that I did not feel would make a difference.

 

[NJN]

Re: Bedding question...not how to, but

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eddybo</div><div class="ubbcode-body">Your right Don knows about as much about bedding as anyone, and he has been very kind to show me his methods many times...I am kinda slow I guess....but he does not bed aluminum bedding block stocks, he scrapes them, or on a quick fix shims them with non compressable shim stock.
I have tried the scrapeing with some sucess but do not have his talent at it, or maybe his persistance I am lacking.</div></div>

You missed the nugget tossed you about lapping.