Convert Marlin 336


Jan 10, 2019
I want to rebarrel a marlin 336 into a different caliber based off a 30-30 case.

Does anyone know where I could find a list of cartridges that are either formed from 30/30 brass or based on the dimensions?
Im not aware of any specific list.....theres a huge slew of cartridges in every caliber (upto 375) that are based on the 30-30 size cases.

What specific calibers are you interested in, its likely theres a common wildcat/proprietary that could be suggested.
I am mainly looking for something one of a kind.

It's mainly to push my creativity
The new Buckhammer is from a .30-30. And if I were to go to the expense, that would be my choice. You would have the only .360 Buckhammer Marlin 336, at least until Ruger gets off of their duffs and gives us one.
Well normally I would not advocate such a thing BUT this 336 survived a tornado and found itself impaled in a field. The wood was busted and barrel bent.

Action is still good

At this point I doubt any harm is being done

That’s a horse of a different color please let us know what you decide me I’d do a 44 mag just to be practical but if living on the edge I’d have to say a 7-30 waters would be sublime!
I don’t mean to be “that guy”, but I would concentrate first on finding someone that can do the job then see what barrels they have available.
If you plan to do it yourself, then I would be looking for what barrels are available that you can buy THEN make a decision on the cartridge.
Marlin made some lever action 219 Zippers which would be interesting to reprise.
I don't know how much trouble it is to form from .30-30 brass and that would be a consideration for any of the old rounds.
Start by using a shell-holder chart to see which other cartridges have compatible rim dimensions. That's partly why I made the decision to rebarrel a Martini-Enfield action with a bent barrel from .303 to .44 Magnum -- they can use the same extractor without alteration.


The only cartridges made from reformed .30-30 brass that I'm using at present are 8.15x46R (requiring rim alteration) and .32-40 (a bit short at the neck.) I doubt you'd want to try either of those.
If you want to go with a wildcat , something like a 30-30 necked up to .338 and blown out would be neat . Or if you can find a .444 marlin bolt to trade out with there are some wildcats like the .375 JDJ that up the power level quite a bit .
There are many choices, but suggestions of a .44 Mag etc. are not good ones - they won’t feed without major modifications. Here are some potential candidates including those already suggested:

.219 Zipper
.224 Donaldson Wasp
.22/30/30 AI
.25-35 WCF
.25-35 AI
7-30 Waters
.30-30 AI
.30 Lever Power
.303 Savage
.307 WCF
.32 Special
.35 Lever Power
.356 WCF
.38-55 WCF
.375 WCF

Finding flat-nosed bullets in the smaller calibers may be a challenge, and some chamberings are quite obsolete. Good luck with your project!

Look into custom dies for true one off cartridges, then think about what you want to do with the gun, then decide. I personally would go 30-30ai, 35-30ai or the 360 buckhammer. Those would all be pretty easy to make feed correctly with available bullets.
357 Herrett is what I would go for. It’s a bit shorter case but you can use .38 spl/357 mag bullets and go from mild to wild. Top end of power would be just shy of 35 rem but with mouse farts all the way down to no recoil at all and limited noise (and add a can for good measure) and you suddenly have a great option for just about anything that’s not higher than you are on the food chain.
how about a 7MM SHOOTING TIMES EASTERNER, it was invented by Layne Simpson of shooting times , its a .307 win. case necked to 7mm and slightly improved , .307 win. brass is supposed to be to be able to be made from .444 Marlin bras. Unfortunately , flat nose 7mm bullets may be hard to find , there were 120 gr. and 139 gr. made by hornady , I suppose there are others .( for the 7/30 waters)
hawk bullets says they will make custom bullets but there's an extra charge
the 120 gr. bullet reportedly moving out at 2900 fps
you can google it if you want , there are plenty of postings
edit : maybe it wasn't invented by Lane Simpson , but the cartridge is credited to shooting times
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You could always go .366 diameter. Bullets in the 286 gr range are common. Pretty sure you would be the first kid on the block to have one. .348 would be another one of calibers. Has the added attraction of Hornady being the only one making bullets.