Cimarron 1851 R-Mason conversion: ammo choice

Arcosdad

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Hello all,
I picked up this little beauty before the Trudeau effect occurred. Open top .38 Sp. My question is about ammo choice. I've been shooting 148 gr wadcutters, very mild. I have a chance to pick up some older Dominion 158 gr LRN and Peters 130 gr FMJ. Is it okay to shoot these in this revolver?

Thx, A/D
 

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The revolver is safe to shoot, with any SAAMI standard .38 Special ammo. Would not recommend shooting Plus-P ammo, though. The mild wadcutter loads you're presently shooting are perfect for it.
 
Arcosdad: Something else you can try that shoots very nicely in the open tops, is .38 Long Colt ammo. Basically, a shortened .38 Special. Brass is available from Starline(if in stock). Otherwise, trim down .38 Special brass. That's how I recycle any with cracked case mouths. A 125-grain LRNFP bullet and 2 grains of Clays for example, makes for a very mild shooting load.
I still load and shoot some Dominion .38 Special brass, made in the 1960's. Excellent stuff.

Al
 
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Man that is BEAUTIFUL.

I’m so jelly. You’ve got my dream gun.
Another pic. It's been professionally shortened to 5 inch from 7.5. This is what Uberti calls the antique finish, much nicer than the bright blue in my opinion.

Thanks for the suggestion on the 38 LC Alex. I'm not a reloader but will watch for it at gun shows. Interestingly I have some 38 Sp 110 gr reloads that a friend did for me that I ran through my SWs that will not chamber in this. Odd.
 

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Arcosdad: Photos of the reloaded rounds would help in diagnosing the problem. If not available though, this info may be useful.

Do the reloaded rounds only go part way in, then stick? To the point where you have to push them into the chamber to make them seat?

When this happens, it's usually the crimp that's at fault

Do you see a noticeable bulge in the case body, just beyond the crimp? If so, the case is over-crimped. This is a fairly common occurrence, with combination bullet seating/crimp dies. Where bullet seating and crimp are carried out in the same operation. That's why it's often recommended to crimp cartridge cases in a separate operation.

Note: If the bulge is not uniform around the entire circumference of the case and appears on one side only, then the bullet was seated crooked.
Which can also cause difficulty in chambering.

The cure: If your reloader friend has access to a Lee Factory Crimp Die(For .38/.357), simply have him run the cartridges through the Lee crimp die, again. Of course, he will need to set up the die to re-crimp the cartridge. Afterwards, check whether the re-crimped rounds will chamber easily. They should.

The Lee Factory Crimp Die has a carbide ring that acts to smooth out any irregularities in the cases..ie: bulges. Leaving behind a nice, smooth crimp.

Hope this helps.

Al
ps: it's also possible that the chamber dimensions of your S&W are slightly more generous, than the Uberti. So, one might accept the over-crimped reloaded round, where the other might not. Something that doesn't occur with factory ammo.
 
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Hi again Alex,
Thanks for your detailed comments. You got me thinking so I took a picture. Factory 130 GR on the right, 110 gr reload on the left. The issue occurs as soon as the bullet enters the chamber. The casing rim hangs up like it's a thou too wide. Some can be worked in and drop in nice once they get moving. This revolver being a 19th century design has the rims exposed not flush like the Smith so as you say the chamfering effect may allow them to drop in easier. Does the picture help in the diagnosis?
 

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Arcosdad: Yes...the photo does offer a lot of information. You are exactly right....the case mouth is too wide.

The reloaded round does not appear to be crimped. Or, not crimped enough. That's why it snags on the chamber mouth. I was thinking about this being a possibility. That's why I requested a photo.

The factory round is crimped. You can see how the case mouth gently tapers into the bullet's crimp groove. Creating a smooth transition. As it should.

Luckily, the fix is simple: Crimp the reload's bullet. That should solve the problem.

Since the reload's bullet appears to be plated... rather than a jacketed bullet, a light crimp is all that is needed. Just enough to hold the bullet securely in place. While permitting smooth chambering.


Hope this helps:

Al
 
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