Author Topic: Which action for converting? (Read 927 times)

cooper · « **on:** July 07, 2004, 06:40:55 AM »

I'm looking to make a Marlin lever action in 40/50 Sharps Straight.

The 40/50 SS case can be made out of 30/40 Krag brass, blown out to 40 cal. with a case length of 1 7/8".

The overall length of the loaded 40/50 cartridge will be around 2.6 to 2.7". The overall length of a 30/30 cartridge is 2.55".

My thinking is to get a used Marlin in 30/30, and then have it rebarreled. If the action is too short for the slightly longer 40/50 round, could the action be modified to handle a longer than standerd round when I have it rebarreled?

Or does Marlin make an other action which would be better for this conversion?

John Traveler · « **Reply #1 on:** July 07, 2004, 07:27:05 AM »

Cooper,

I'd look at the Marlin M1895 chambered for .444 Marlin or .45-70 for your conversion. Both are based on the M336 of course, but with the bolt face and action opened up for the longer rounds.

The concern is that the M336 in .30-30 might not handle the longer rounds, giving you ejection problems, plus the need to open up the bolt face and extractor to handle the .30-40 rim size. Extraction of loaded .45-70 with longer bullets is a problem in the M1895. Also, the magazine tube may be too small in diameter. The .444 should be close to the bolt face and extractor you need, plus the action length and magazine tube are correct.

The plus side of an M336 conversion is the lower action cost. The negative is more machining work required.

Let us know how the conversion works out.

jackfish · « **Reply #2 on:** July 07, 2004, 08:39:18 AM »

The Marlin 336 or 444 would be the best Marlin actions to use because of the rim diameter of the 303 British and 30-40 Krag at .540" and .545" respectively. Cases can be formed from the 303 British and 30-40 Krag. The carrier and extractor can be modified on the Marlin 336/444/1895 to accommodate the cycling of cartridges up to 2.75" in length.

cooper · « **Reply #3 on:** July 09, 2004, 06:45:12 AM »

Thanks for the info, guys. I guess I wasn't thinking - I automatically just thought that the 30/30 rim size would be compatible with the 30/40 Krag or 303 British - but you are right, of course - the 444 or 45/70 bolt face is a much better match, along with the magazine tube being the correct size.

Now to find a reaasonably-priced, used 444 or 45/70.

One more question - any recommendation as to a good Marlin gunsmith?

marlinman93 · « **Reply #4 on:** July 10, 2004, 12:25:35 PM »

The larger bolt face of the model 1895 would actually make it a poor choice to use for this conversion. The .600" rim diameter is much larger than the .40-50 Sharps, or the base case of .30-40 Krag, so the extractor would not work, nor would the bolt face fit correctly.
The 444 would work, but since these guns are usually higher priced, and it would still require some opening of the bolt face, it wouldn't be my first choice either. If you have to open up the bolt face a little or a bit more, the cost is the same, so using the 336 is a better choice.
The 336 is the same basic action, and they can be found in rough shape for as little as $125, or maybe less. That leaves a lot of extra money for your project, rather than the initial purchase.
The cartridge you plan on using is not a high pressure cartridge, so any Marlin 336 would be more than adequate.
Hope this helps.

Wildcat Crazy · « **Reply #5 on:** August 02, 2004, 03:30:32 AM »

The .303 Br.will function through the 336 magazine OK,however the rim jams in the receiver as the shell is being lifted,the feed rails would need to be opened up a bit.

WC