27-s strength?

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Bbarcroft
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Location: Mansfield, OH

27-s strength?

Post by Bbarcroft »

I happened across a nice little 27-s in great condition, chambered in .25-20, that I ended up bringing home. Unsure of build date (I don't have the gun in front of me to check the S/N), but the pics on my phone show the barrel as 0marked: Special Smokeless Steel along with: Marlin Firearms Co. New-Haven CT. U.S.A. with a series of patent dates, the last one being Nov. 29, 1904.

My question is... being as this chambering is mostly obsolete, with factory ammo rare and expensive, I've geared up to reload for it. Factory black powder loads averaged an 86gr bullet @ 1450fps where advertised smokless "high velocity" loadings claimed over 1700fps for the same bullet.

Is this 86gr 1700+fps diet detrimental to the 27-s action, or is the design stout enough to handle it? I have sourced 180 cases, 500 75gr Speer SJFP bullets and 250 70gr gas-checked cast boolits. I'm going to start with slower-burning powders like 4227 and 4198, as they offer the same velocities without the pressure of faster powders like Red Dot and Unique.

Published load data shows velocities at 1800fps or so with either bullet. Is the rifle up to it, or should I back the loads off a touch? Plans for the rifle are to use it as a cool groundhog whacker on the farm, along with informal silhouette and 2-liter busting out to about 200 yards.
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marlinman93
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Re: 27-s strength?

Post by marlinman93 »

The .25-20 came out right near the end of black powder, and the Model 27 has probably seen little to no black powder in it's life. The fact they are still around and still shooting great pretty much tells the story of how strong they are.
I'd personally not have any issue shooting factory ammo in them if I found it. But I load all my old guns down to velocities under 1500 fps, just because I like those loads, and they shoot just fine at lower velocities. Not sure your gun will shoot too well with 4198, but 4227 might work OK. I think Unique, or 2400 would be better choices and wont be too much pressure if you keep the charges down where they should be.
Marlin lever actions 1870's-WWI, Ballards, and single shot rifles!
Bbarcroft
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Location: Mansfield, OH

Re: 27-s strength?

Post by Bbarcroft »

I chose to start with 4227 and 4198 after browsing the castboolit forums and looking over the powder supplier pages and my loading manuals. The general consensus is the slower rifle powders produced the same or slightly higher velocities when compared to the faster-burning pistol powders, while exibiting roughly 10% lower peak pressures.
As not knowing the 27-s pressure "rating" (as compared to, say a Model 1894), my goal was to extract the little cartridge's potential while limiting the pressures exerted on the rifle.
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marlinman93
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Re: 27-s strength?

Post by marlinman93 »

4227 isn't a bad choice, but I personally found 4198 just left too much unburned powder in the bore, and the only way to get it to burn clean in a .25-20 was to push the loads hotter. So mild loads just didn't work with 4198. 4227 is a better choice, and it and 2400 are very close to the same burn rate. 2400 is just a bit warmer, and cleaner.
Marlin lever actions 1870's-WWI, Ballards, and single shot rifles!
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