threads stripped, long story- need advice.

Silly_Ghillie

Well-Known Member
Joined
Oct 2, 2018
Messages
81
Location
colorado
I looked for an existing conversation on this and couldn’t find a good one. Some didn’t have the right answer for me so here we are.

I have a Savage 110 with some thread issues in the scope base holes. My nearest gunsmith is over 150 miles away, so help on this matter will be surely appreciated. This is a long story, and I want to preface the situation that way I don’t have to answer inevitable questions I know will surely come.

So, I tear down the rifle for a rebuild. I get all the way to the scope base and the holes are full of old blue thread lock. So I go out of my way to buy a tap from North Bay Tool in 8-40. Now, I know for a FACT that the existing screws are in this pitch. I have a nifty little tool that reads standard scope base screw sizes- so, I buy a tap, replacement rail and a screw kit from Brownells. All is Good.

About a week later, I get the time to start doing receiver work and start tapping the holes. I notice nothing out of the ordinary other than a slight tension- I thought it was the copious amount of Loctite I had used. I get to the point where I am threading in the new scope base screws and I notice an ever so slight increase in the amount of slop in the threads. I don't see any shavings, I get to the last hole closest to the barrel end of the receiver and the screw BARELY engages with the threads. I look deeper and the threads are trashed… I used every method at my disposal to do this the right way, but somehow, I screwed up. whether I did it while tapping or before that I don't know.

I immediately start to panic. I look at the tap, “yes, it’s the right pitch”, I look at the screws and test them- “they are all the right pitch”. I put the tap in the thread tool and it wont thread…. The height of the cutting edge of the tap threads is about .015 over the original threads… never in my life have I ever had a tap that didn’t work right or was the wrong size, so I didn’t even think to check it in the thread gauge until it was too late.

So, here is my conundrum. I mounted the base as carefully as I could, using 30ish inch pounds as recommended by the manufacture of the base. I tightened the screw in the bad hole as tight as I felt was safe, and then used JB weld on the base and receiver surfaces to hopefully mitigate movement. I have no doubt that this will more than likely hold for now. The base was well fitting before so no worry on misalignment.

Now I don’t ever intend on selling or getting rid of this rifle. But, in the case that I want to take the base off and repair it properly, what options do I have realistically? 8-40 is usually the next size up after a stripped #6 thread scope base hole, but what if the 8-40 hole is stripped? Do you go up to 10-32? Do you fill in the hole with cold weld and drill another one- having to customize every scope base to fit the new hole pattern?

I am up for suggestions. I would love to do something like weld the base on the receiver, but I already know you cannot do that without weakening the receiver. Any ideas that will help me fix my blunder? anything I can expect my gunsmith (last resort) to try and do?
 

TexSavage

Well-Known Member
LRH Team Member
Joined
Jul 30, 2006
Messages
357
Location
Amarillo, Texas
Well not sure if this helps, but I'll relay what my brother and I did with the same kind of situation only on a larger scale. We had a 6 cylinder Cat engine in a Stiger tractor we had to overhaul. One of the head bolts stripped out somehow during disassembly. We first cleaned the hole in the block thoroughly and degreased it twice. Did the same thing to the bolt. We then mixed up JB Weld, filled the hole with the JB Weld, greased up the bolt so the JB Weld would not stick to the threads and tightened it down. We wiped up all excess JB Weld as it oozed out making sure the bottom of the bolt stayed clear of any contact with the JB Weld. Of course we also applied a little grease on it as a safety. We then let it set until hardened and then removed the bolt. We then allowed it to cure for 24 hours. After that we mounted the head and proceeded to tighten the bolt to about 150 Foot Pounds and never looked back. Ran that old tractor for about three years after that with no issues and sold it when we left farming. I know it was still in use several years later. Narry a problem. Now, that was one option, our second was a heli-coil but we were a ways from one so help JB Weld. Key was making sure parts were clean and no grease inside the hole.
 

Silly_Ghillie

Well-Known Member
Joined
Oct 2, 2018
Messages
81
Location
colorado
Thanks Tex, if it doesn't hold up with how I have it now I will try that. I think inevitably I will take it to a smith and have him drill em' all out and tap them to 10-32. I would do it myself but I am not taking any chances with my recent luck.
 

Dean2

Well-Known Member
Joined
Jul 31, 2010
Messages
1,277
Location
Alberta
Two reasonable options. Re-thread it properly or if you don't mind a permanently mounted rail, use some Devcon on the base, receiver and holes. Do not apply release agent, make sure metal is decreased using acetone. Base will NEVER move. If you must get it off, heat will do the job.
 

BULLBLASTER

Well-Known Member
Joined
Feb 6, 2012
Messages
139
Location
spokane wa
If your using a 1 piece base like a pic rail, I wouldn’t worry much about only using 3 screws to hold it on. Lots of the front hole screws only hold on by a thread or less anyhow.
 

SealT5

Well-Known Member
Joined
Jan 11, 2016
Messages
872
I agree with the above. Put a 1 piece rail on it and get 3 screws properly torqued. Doubt you will ever have an issue
 

Silly_Ghillie

Well-Known Member
Joined
Oct 2, 2018
Messages
81
Location
colorado
Yeah, I just Globbed the three rear with blue thread locker and slapped it on with a sprinkle of JB at 25 in-lb and it feels solid. Its a one piece NF 20 MOA- I was pleasantly surprised on how well those are machined, I did the paper test on the base and I couldn't get a single piece in under the base.
To be honest, I doubt that base will ever come off unless some freak accident requires me to remove it.
Thanks for the input fella's, much appreciated.
 
Warning! This thread is more than 4 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.
Top