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jawjadawg
12-16-2010, 08:08 AM
I have tried searching for this, but it is buried so I will ask in a way that will be easy for someone else to find.

I would also like to know how much of the case to leave behind the rim.

Finally, is there any value in using a 357 magnum case on my magnum rifles instead of the 38spl I will use on the 473 and 378 bolts? :) j/k

82boy
12-16-2010, 12:00 PM
I would also like to know how much of the case to leave behind the rim.


Cut the case down as far as you can go. The case head has a thick spot behind it, you should cut down to that level. The amount behind the rim is unimportant.



Finally, is there any value in using a 357 magnum case on my magnum rifles instead of the 38spl I will use on the 473 and 378 bolts? :) j/k


Nope, none at all.

"38 spl lift kit ball bearing size."

One that fits down in the hole. You just want a small amount of the bearing surface sitting above the case.

jawjadawg
12-16-2010, 12:24 PM
I would also like to know how much of the case to leave behind the rim.


Cut the case down as far as you can go. The case head has a thick spot behind it, you should cut down to that level. The amount behind the rim is unimportant.

Thank you



Finally, is there any value in using a 357 magnum case on my magnum rifles instead of the 38spl I will use on the 473 and 378 bolts? :) j/k


Nope, none at all.

j/k is internet for "just joking"

"38 spl lift kit ball bearing size."

One that fits down in the hole. You just want a small amount of the bearing surface sitting above the case.


Okay. Clearly I am not a ball bearing expert, but I assumed a person would want a ball bearing that would fit snug where the primer was removed. I guess I asked a stupid question. Those tend to yield similar answers. Clearly a ball bearing that is larger than the hole will not work. Am I incorrect that a ball bearing that is smaller than the hole will not work because it will move or even fall out. So I guess a more intelligent question would have been asking what size the hole is so that I can get a ball bearing to match. That would seem to avoid answers such as, "One that fits", or is there really no problem with using a ball bearing that is smaller than the hole?

82boy
12-16-2010, 12:46 PM
Nope one that fits is the correct answer. I just took a case up to the bike shop and found some that fit the case will little amount of slop. You are going to use epoxy to cement them in, and the epoxy will take out the slop, and hold them in place.

jawjadawg
12-16-2010, 01:20 PM
Nope one that fits is the correct answer. I just took a case up to the bike shop and found some that fit the case will little amount of slop. You are going to use epoxy to cement them in, and the epoxy will take out the slop, and hold them in place.


Ahh...epoxy. Now it all comes together. Than you, sir.

mr45acp2u
12-16-2010, 03:28 PM
Epoxy, silicone, grease, gravity, there are lots of things you can use to hold it in place while you reasemble. ;D

Cycler
12-16-2010, 04:51 PM
One experiment is worth a thousand guesses. I just decapped a .38 Sp case and, since I also work on bicycles, I have all of the common bearing ball sizes on hand.

It turns out a 5/32" ball fits into the primer pocket and just a little projects above the case head. So I expect that's the size you need.

The next size up is 3/16" and it's too large to fit.

Darth1
12-17-2010, 12:55 AM
I used a 22-250 case because the rim size is only a few thousands larger that the OD of the sleeve. I had to "work down" the remainder of the case though. I used a .125 (1/8") ball and let the ball set in the flash hole, which I put a small radius in to hold the ball, because the exposure of the ball was only about .015" above the rim of the 22-250 case. After cycling the action many times, I can see a small "print" where the ball is contacting with the bolt. This tells me that the ball is staying centered in the flash hole. Also my total increase in length was about .075". I added a modified washer BETWEEN the bolt handle and the bolt the same thickness to make up for the increase caused by the bearing/22-250 assembly to keep "all things equal".

There is pressure on the ball at all times, so I saw no need to glue the ball in place, once assembled, I believe it will stay there. Also it's "trapped" in the primer pocket.

Just another way of accomplishing the same goal ... I guess.