1894 Cowboy .45 Colt Breech Blowback

What the name implies

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1894 Cowboy .45 Colt Breech Blowback

Post by thejhereg »

Morning All,

I've got the same problem as others have mentioned below with excessive blowback on the cases 2/3 the way back on the case. It's occured with factory-new Black Hills and Winchester Cowboy loads, but only happened to a very slight degree with Magtech Cowboy loads (that a friend gave to me as a gift, that he uses in his Taurus SAA).

I got the rifle for Christmas from my Dad (unfortunately he lives in Houston, while I'm in Denver) and he's already called Carter Country down in Conroe, TX where he got it and they said they'd take a look at it and 'make it right'... they said they'd replace it and take care of it with Marlin, themselves. The unfortunate part in this is that it seems to be a problem in production and/or quality control rather than just a 'onsies', 'twosies' problem, especially if it's happening all over. My Dad's going to have them test-fire any possible replacement with the offending ammo and see if it does the same thing.

We compared the amount of play of a round in the chamber between the Marlin 1894 and a Winchester 1894 .45 and in the Winchester there was NO movement laterally of the case in the breech at all. In the Marlin there was probably a couple hundredths, plus, of play in the chamber... no we didn't have a mic at the time to check the play amount, but I'm going back down to my house this afternoon to get the paperwork, receipt, box, etc. and am going to mic the breech and the casings and want to compare them. I just would never have thought I'd see something like this on a Marlin... a Winchester, maybe, but not on a Marlin.

1) Has this only been happening recently (i.e. the only posts I've seen have been since late October to early November) and could it be a dull tool in the CNC machine they're using to cut the breeches in only newer production or has it been happening a long while?

2) I'd guess Marlin's aware of the problem, but do they acknowledge how wide-spread it is? Is there a Serial Number range or production date I can look for that DOESN'T have the problem?

3) I don't want to just send it to Marlin to 'Make It Right' which I'm sure they'd gleefully do to avoid having a problem with a popular, higher-volume sales dealer. However if there's this wide-spread a problem with the weapon and they 'all do it', then it needs to get fixed at a higher level in either their manufacturing process or their QC process and they need to stop fixing it only when someone notices they've got a problem with one of their rifles.

4) If the .45 Colt does it, do the other Cowboy (Hex Barrel) rifles in the .38/.357 and the .44 Mag/S&W do it as well?

5) Do the Standard 1894 rifles in those calibers with the round barrels have the same tendencies or is it only the hex barrels and the way the chambers are cut in them that have the problems?

6) What process does Marlin go through to 'fix it' and make it right? Replace the whole barrel or do they weld-up and then re-cut the chamber?

7) Has anyone chrony'd rounds of the .45/.357 and .38/.44 Mag out of the 18" barrels? If so what are they getting with factory ammo for muzzle velocities?

In and un-related question, my Father's got his old, probably a model 1892 hex-barrel .22LR Marlin, that has a barrel that's severely pitted and worn, is it possible to get that bored and sleeved to spec.?

Anyway, thanks for the time all and Happy New Year!!

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Re: 1894 Cowboy .45 Colt Breech Blowback

Post by SteveW »

I don't use factory ammo but I ger a little over 2100 fps from 125 grain jacketed bullets from my 1894CP. While there may be a machining/tolerance issue, I feel a lot of the problem is light-loading the 45 Colt. It was designed as a black powder load with a full case. Have you tried a few rounds with black powder or a sub? Even with a chamber out of spec, a stouter load will cause the case to expand and eliminate smoked brass and blow back in many cases.

For relining, there are a couple companies doing the work. Redmans of Washington St is one. SW
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Re: 1894 Cowboy .45 Colt Breech Blowback

Post by Jim D »

I agree with Steve. Light loads don't seal as well as heavier loads. Or it could be a slightly too large of a chamber diameter. It can happen when they start using a new reamer. Reamers wear down over the course of reaming many chambers, so new ones are cut to maximum dimensions, and are used until they wear down to minimum dimensions. Have you looked at the cases from the heavier loads? If you see noticable expansion or bulging towards the base, send it back and Marlin will put a new barrel on it.

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Re: 1894 Cowboy .45 Colt Breech Blowback

Post by Four-Eyed Buck »

With Cowboy loads, some blowback is normal. Using the 250's help some and some have gone to .454's. Brass type plays in this as well. Starline and Remington tends to have more blowback than Winchester. They must be stiffer than the Winchester. Make sure if you're reloading that you put a stout crimp on it.............Buck 8) :wink:
If Marlin made SA revolvers, I'd be shooting those, too!!!
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Re: 1894 Cowboy .45 Colt Breech Blowback

Post by BUSHMAN79 »

This is another example of why .45 Colt isn't as good as .44-40 in a rifle. Even with full power black powder loads in my revolver, I occasionally get a sooty case with Remington brass. It's too bad the discontinued the .44-40 in the cowboy rifle.
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Re: 1894 Cowboy .45 Colt Breech Blowback

Post by prairie_buck »

I have had the same problem with a couple of rifles (marlin '94's and Puma win. '92's in .44 Rem Mag.

We started by using Cerosafe to cast the chamber. We found that the chambers were with specification. Those we eliminate the firearms as being the problems.

Next we tried a number of types of factory ammo in both .44sp and .44mag. What we learned was the lower level loads were not expanding the brass enough for a good chamber seal. These was very prevailant with CAS level loads.

Next we played with reloads at both CAS and full house loads. Here the problem was again confirmed to be the loads.

The question that remained was how to produce a CAS level load that would expand the case and achieve a seal.

The solution was to load to the maximum CAS feet per second. This meant that one had to have a different load for your revolver and for your rifle. Yes a PITA! The next trials were to make changes to the loading process that might help with the problem. Tried things like mag primers, rifle primers, faster powders. In a modern 1894CBL, we never got the .44spl Winchester Cowboy loads to seal.

The result is that it could not be total eliminated BUT it could be reduced by using a FIRM crimp with a Lee Factory Crimp Die. DO NOT USE THIS FIRM CRIMP ON ANYTHING BUT REDUCED LOADS!!!

Hope this helps.

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Re: 1894 Cowboy .45 Colt Breech Blowback

Post by seven_bears »


I was in the middle of a cowboy shoot and I lost a screw on the receiver side of the gun located next to the serial number. Does anyone perhaps know the name of this screw or where I could find a new one to order?

Any help or suggestions are greatly appreciated! Stay safe and well,

Seven Bears
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