11 June 2004, 06:22
DeltaHunterPre-64 Mod 70 - buggered scope base screw hole
The rearmost scope base screw hole on my new pre-64 model 70 is somewhat stripped out. All the other screw holes look fine. I can install a screw in it, but I'm not sure how well it's going to hold over the long haul. My Talley mounts won't arrive for a few more days. I guess I'll find out when I install the rear base if it's going to allow me to tighten it down enough.
If this screw hole strips out when I install the base (or at some later time), what are my options? Can I drill it out and re-tap it to accept a larger screw? If so, what would be the best screw size. Also, what about the Talley base. I suppose it would have to be modified to accept a larger screw and screw head.
I don't know if this will be a problem or not, but in case it is I would like to know now how to handle it and I'd appreciate any input.
I bought a tap from brownells to clean up the crud in the holes of a old pre64 I got. One rear hole the top couple threads were stripped , but there was plenty of thread left bellow, I used longer screws and trimmed them to fit.
Id suggest at least running a standard size tab in them to clean the threads so the threads dont get wreaked from debree and grit.
6/48 is standard 8/40 is the next size
11 June 2004, 07:29
free_minerif you go to 8x40 screws you will need to counterbore the bases as well. This is a good option on a rough duty rifle anyways.
A quick do-it-yourself fix is from brownells, they sell an oversize 6x48 tap and screws that will clean up stripped 6x48 threads, and the screws will fit in the original counterbored hole in the base
You might try the "Oversized 6-48 Screws" Brownells offers for this situation.
Page 146 of Catalog 56
Second suggestion would be a drop of good epoxy in the hole and wind it down tight- this is of course if you "really like" those Talleys...
Oh what we go through to keep those Pre 64s workin'...
11 June 2004, 10:17
DeltaHunterThanks a bunch guys. That oversize tap and screw kit just might be the ticket.
Now Thats good advice , "epoxy it" , Yeah glue the sonabitch. Yea,,, then rap some ductape around the scope , that will hold it. Come on bubba!
12 June 2004, 02:07
UltramanI probably would not epoxy but I would use locktite red or threadlocker. While its classified as non-removable, a minute or two with a soldering pen applied to the screw head and it will release. Thats the way I do all mine
12 June 2004, 02:52
Jim KobeIf it is a big caliber, a magnum or whatever, do your self a favor and have them all done to 8-40's. Are you sure it is the hole and not the screw that is stripped? Usually, the screw is the offense not the hole. And, as stated earlier, there is probably more thread down below. Try the longer screw first.
12 June 2004, 05:20
JohnlyI picked up a old 700 BDL in 222 with a similar problem, except that it was the forward base hole that was buggered. I thought about going the 6-48 oversize route or tapping all the screws out to 8-40, but instead I purchased a B-Square one piece base that had provisions for 4 mounting screws, and only used 3. I figure that if a three hole Leupold one piece base works on my 7 1/2lb 375 H&H, I'm not taking too much of a risk using only three mounting screws on my 222.<BG>
16 June 2004, 05:40
DeltaHunterThanks again for suggesting the oversize 6-48 screws and tap. I re-tapped the hole with the oversized tap and used the new screw. I also had to make the hole in the scope base larger to accomodate the slightly larger screw. It seems to have worked out fine.