Model 70 Stripped Bolt Spline Repair
Has anyone tried Red 263 Loctite or epoxy to repair a stripped Model 70 bolt handle spline?
If not can you describe the procedure for silver soldering or brazing?
I guess I need to reply to this; WHAT???
Have only dealt w/one, I sent it back to Winchester (Browning) for repair. I would give Dan Armstrong @ Accutig a call. I know Remington bolts are not the same but ,he might be able to help. I have him do all my bolt handle welds and his work is flawless, he knows what he's doing. Possible the spline to body fit can be welded.
The collared Win 70 bolt handle is a poor excuse for a casting.
Do not attempt to silver solder the handle-
Location(fwd & aft) isn't a problem as there is a shoulder turned into the bolt body.
Align the firing pin cocking cam surface of the bolt handle & the bolt body & fusion TIG weld the seam at the handle/bolt body shoulder.
Been there done 100's!!
Kinda figured Dan would see this...take his word for it and send it to him, problem solved, the right way! I agree w/Dan description of the splined collar arrangement that Winchester uses but I prefer much more colorful language.
Herb Coates... HC Precision
I read somewhere that................
There was a wafer of copper put on that bolt body, then the handle was pushed on w/extreme pressure.
Then there was a high-voltage plasma shot, which was supposed to melt the copper, making the two parts wedded for life.
Another tale found to be an illusion......
Kinda makes a guy like his pre 64's doesn't it.
You got it.
And, check your PM, you got it.
I'm unaware of this problem, which model 70 is this common too ?
Sorry, I didn't receive a reply for a couple of days so I proceeded on my own.
I talked with an engineer from Loctite and he recommended Loctite 660 but it only has 2500 PSI shear strength so I ruled that out based on silver solder's 40K+ PSI.
I talked with an technician from Brownells familiar with the repair and he recommended their 55% silver solder........definitely not the 5%. I couldn't wait for that to arrive so I used Silva-Safety 55% silver solder.
I must admit I was hesitant to proceed but since this is my personal rifle so I forged ahead......I leave for an elk hunt on Sunday.
I lined up the bolt and the handle in the remaining splines using the serial number etched across the handle collar and the bolt body and tested that in the action with the firing pin assembly in place to assure alignment.
I made an aluminum clamp the length of the bolt body which also acted as a heat sink and I wrapped the bolt head and handle in wet rags. After removing the firing pin assembly I pulled the bolt collar away from the bolt shoulder about .100 to allow access for the silver solder to penetrate under the collar. I heated the collar and rear of the bolt and the silver solder sucked in nice and neat. After applying the silver solder I tapped the collar home against the shoulder while still holding the torch on the collar. I applied most of the heat to the under side of the collar to avoid overheating the handle and bluing.
After removing the scale with a Dremel and wire brush I there was a little clean up to do on the lathe to remove some excess solder that came out when the collar was tapped home to the bolt shoulder. The excess probably resulted from my touching the solder twice......once may have been enough. I used about 1 inch of a 1/16 rod.
Everything went as planned, the bolt head never got more warm to the touch and all bluing was preserved on the bolt handle.
Dan can you comment further about not silver soldering this repair? My repair appears to be very strong and neat. Does your TIG repair method require lathe clean up?
Thanks everyone for your replies..........any further comments are welcome.
Based on an article in Rifle Sept 2006 this appears to be a common problem with Model 70's. I recall the author, Barness???, stated that most Model 70's used for dangerous game are re-soldered or maybe TIG welded by Dan above. See my further post below.
I hope it doesn't fail you during the hunt. You have a backup I trust.
This problem is only present on post 64's. The back end of the bolt is knurled and a copper alloy brazing washer is placed on the bolt before the handle is pressed on. Then the bolt is furnace brazed at about 2000°. Because of the high temp, subsequent heat treating of the bolt is not a problem.
Is that method of bolt handle attachment common to push feed , control round feed or both ?