10mm GP100 conversions?

[Silvercreek Farmer]

Seems like the 10mm GP100 might be a good candidate for a conversion to something like a 401 Powermag. I saw where Jeff Quinn did a write up on one converted to 10mm mag. Any other conversions brewing out there?

[Groo]

Groo here
The problem with anything bigger than 10mm/mag is the rim and case size .
With the original cylinder the metal gets kinda thin.
In a 5 shot ,,, that is somewhat different.
10mm mag would be ok as long as you get the correct moon clips to head space on the clip when shooting 10mm or 40S&W.
If you could get another cylinder from Ruger ,one 10mm mag and one 10mm and with thicker clips 40.

[725]

A 10m revolver sounds like neat deal. The 10 is plenty powerful for my purposes.

[Piedmont]

At some point of enlarging the hole that forcing cone becomes an issue. It disturbs me that multiple users are cracking their GP-100 .44 (which of course is a .43) forcing cones and at least one with loads that aren't that warm. You would think Ruger would have given that area special attention since they had to know the problems S&W had with their 5 shot L frame .44 special.

It might be best to just buy one in 10mm and leave it as-is, but it sure would be nice to have a rimmed case, for crimping if no other reason. Factories are only going to want to chamber in factory cartridges. Ruger knows there is a .41 Magnum. I wonder if that would work if they used a 5 shot cylinder?

[Boogieman]

Ruger now has a GP100 in 10mm which has SAAMI max. of 37,500 psi. The 41mag. is rated at 35,000 psi . The groove dia. is only .010 larger in the 41mag. which makes the sides of the forcing cone a whole .005" thinner .

[rking22]

When Ruger released the 6 shot 10mm it gave me a good feeling for acceptable pressure for my 41 special. Now, I just looked at a picture of the barrel extension/ forcing cone area on a 10mm. It shows a hex shape and notable thickness. Does anyone have one to verify that detail? Ruger may have solved the thin forcing cone sitiuation and a 41 mag is in the wings! I have the 44special and it seems to have a " normal" extension
https://revolverguy.com/ruger-10mm-gp100/
Shows a picture and it looks to be hex sided and bigger than the threaded. A sleeve /2 piece ??

[Piedmont]

I'm seeming to vaguely remember that David Clements would convert GP 100s to .41 special, and 10mm, but not .41 Magnum. Does anyone else remember that?

[megasupermagnum]

Wouldn't it be easier to go up in thread size for the barrel shank? Don't give the engineers any more reason to get fancy with a simple solution.

[rking22]

Piedmont, that is correct. The 41 Special is "Just Right" for the GP100!

[megasupermagnum]

I'm sure 41 special is cool, but I don't see why Ruger can't make a plain old 41 magnum with just a little engineering. Gary Reeder converts them to 41 mag, although he has some people that love him, some that hate his guts. Not a lot in the middle, and a lot of bad reviews. As I understand he lengthens the frame some, installs a custom barrel and cylinder and there you go. Too bad Ruger can't come out with a "super GP" frame that can handle full 41 mag, 357 max, etc.

[osteodoc08]

I'm seeming to vaguely remember that David Clements would convert GP 100s to .41 special, and 10mm, but not .41 Magnum. Does anyone else remember that?

He did. Unfortunately he has focused on the Ruger SA market for a while now. Last I spoke to him a few months ago, he was going to be picking up a few Marlin 1894 custom projects. He’s been backlogged a long time, but I continue to pester him. I’ve been very satisfied with his work.

If Smith can engineer an L frame 44, Ruger can certainly produce a GP 5 shot in 41 Mag/Special and 44 Mag. We already have the 44 special.

[rking22]

231842
Figured out how to show the picture, is this Ruger's solution to higher pressures in the big boreGP100s? My 44special does not look like that, very thin at the bottom.

[Silvercreek Farmer]

Interesting. What does the muzzle look like?
231842
Figured out how to show the picture, is this Ruger's solution to higher pressures in the big boreGP100s? My 44special does not look like that, very thin at the bottom.

[Piedmont]

If Smith can engineer an L frame 44, Ruger can certainly produce a GP 5 shot in 41 Mag/Special and 44 Mag. We already have the 44 special.
Well that is the whole point. Of course they can reengineer it, but they chose not to and we have Ruger .44 Special GP-100s cracking forcing cones, just like the original S&W L frames did. Ruger dropped the ball, again.

[rking22]

231856

Looks "normal", that is from the link I posted a few days ago. Seems they have done something to support the forcing cone area. I have an L frame 696 and ,so far, no issues. I shoot Skeeter loads in both my y96 and GP100. I considered srinking a support ring around the area on my y96 but there was no room above the has shield. I have seen NO reference to a beefed up forcing cone on any of the Ruger adds or reviews except the one I referenced. And no explanation there! Considering the most issues with the 696 were light bullets and fast loads, Ruger seems to have tried to "do something".

[megasupermagnum]

Well that is the whole point. Of course they can reengineer it, but they chose not to and we have Ruger .44 Special GP-100s cracking forcing cones, just like the original S&W L frames did. Ruger dropped the ball, again.

I don't have the measurements on either the L frame or GP100, but to my eye, the GP100 forcing cone looks thicker, at least adequate for the job. I don't think they are cracking left and right. I've heard a couple cases, but I can't even find them when searching "gp100 cracked forcing cone". The only thing that comes up is a 357 mag, shooting no less than the infamous 125 grain bullets.

[Groo]

Groo here
The 10mm/40/.410cal bullet is best for a 6 shot application in L frame guns...
Ruger was trying to get most from a frame in production.
The 44 spec was a test to see how far people would push things.[a little too far!!!]
I doubt there will be a 44 mag , but a 41 spec [like a 480 ruger] you might see....
IF the shooters have no problems shooting "nuclear" level loads, because some will try to mag it a 41 mag.
The difference and lack of rim on the 10mmgives max steel in the cylinder and barrel of a 6 shot.
If ruger [or others] get around the moonclip thickness problem, I would nor be supprised to see a 10mm mag/10mm/40 from a distributer.

[High Desert Hunter]

Seems to me a 10mm is pretty close to a 41 Special as it is. I know in the 1911 platform I am getting over 1200fps from a 5" barrel and 202gr FNGC bullet, of course it is .010" smaller. I cracked the barrel on a NM Super Blackhawk a few years back, was informed that it had likely stress cracked from being over tightened during assembly, took a bit over 5000 rounds for the problem to show itself.

[RJM52]

Several years ago I picked up a very nice 1968 vintage Colt Trooper with a 4" barrel...have been tempted to send it to Jack Huntington for a .41 Special conversion as I rarely shoot .357....

There were a few factory Pythons made in .41 Magnum and there was also a gunsmith in East Texas that did conversions. I figure if a Python will run a .41 Magnum than a Trooper that is the identical gun without the fancy barrel should work great in .41 Special...

Bob