Marlin 36 RPP Lever-Action - As Powerful as a .356 Win with Safe Pressures

by Adam Devine

Already in 2018, we have a dozen customer builds on the schedule for a Marlin 36 RPP custom-built lever-action. Some plan to handload their 36 RPP ammo using a 36 RPP Lee Precision Die Set and our load data. Others will simply buy 36 RPP ammo from our partner TAC Munitions. So far, it's turning out to be an exciting year for the 36 RPP!

As powerful as the .356 Win with safe pressures. More Power than Any Marlin Levergun except the 450M. More Range than any Marlin Levergun except the .338 ME.

So what is the 36 RPP? Well, for one thing it seems silly, given the performance of this thing, to round .358” down to .35 rather than up to .36. For another, there is some Texas Ranger heritage entwined with the .36, and we like that. And, there is a phenomenally good Texas small batch bourbon from Ranger Creek Brewing & Distillery that bears the .36 moniker, so this will make a triumvirate.

Custom Marlin 336 .35 Rem .36 Caliber

To address the inevitable question: “if I want a more powerful .35, why wouldn’t I just go to a .356 Win?“ Well, you could, and plenty have, and it is a fine cartridge. But it is severely hobbled by scarcity of brass and ammo. And there are many who feel squeamish about the .356’s chamber pressure of 52kpsi. I was one, but through all of the testing and builds that we did in 2017, we've found that the 336 still has adequate safety at those pressures.

One nifty aspect of our the .36 RPP is that it can deliver .356 Win performance while operating at comparatively tame .30-30 pressures. But what it can do at 50,000 psi is truly impressive.

Without further ado, here’s the skinny:

First, the juicy performance figures. From our test rifle’s 22.5” bbl, safe, accurate loads have achieved the following: 1) with Speer’s 180gr FP, a MV of 2800fps (3133 ft/lbs of energy); 2) with Speer’s 220gr FP, a MV of 2500fps (3052 ft/lbs energy); with Hornady’s 200gr FTX, a MV of 2635fps (3083 ft/lbs energy). Note that we believe the terminal performance of the 200 FTX will likely be compromised by these high velocities.

In short, the .36 RPP can add nearly 400fps to commercial .35 Rem loadings, and well over 100fps to .356 Win loads.

Accuracy in our test rifle’s match-grade Douglas barrel was stellar, with nearly all test loads shooting sub-MOA before the barrel was even broken in. Some loads shot closer to ½ MOA.

  • Parent case to the .36 RPP is the .35 Whelen. Not ubiquitous by any means, but readily available. Hornady makes quality brass for the palatable price of $.75/ea.
  • .36 RPP brass is formed by trimming and full sizing Whelen brass. No fire forming, reaming, or neck turning is necessary (or 20 rounds of boxed ammo is available for $34)
  • Max COAL is 2.72”. Case volume is 62gr H2O.
  • Offers more power than any commercial lever gun cartridge except the .450 Marlin. Yes, this includes the mighty .444 and .45-70, as well as the .338 ME and its bolt action analog, the venerable .30-06.
  • Offers more range than any commercial lever gun cartridge except the .338 ME

* Donor rifles are Marlin 336s chambered in 30-30 or .35 REM—readily and cheaply available both new and used.

* Conversions require action stretching, but for the budget minded the factory barrel may be retained, and for those who want the ultimate in range and accuracy a longer match-grade Douglas barrel blank can be chambered and fitted.

* Lee Precision 3 Die Set: .358 Seating die, 36 RPP full-length FL sizing die, modified Crimp Die ($95)

* TAC Munitions .36 RPP, Speer HC ammo, 20 rounds ($34)

Find out more about the Marlin 36 RPP lever-action!