Which mold for a Marlin 336 30-30 micro groove?

[smkummer]

A friend just shot his 336 for the first time in many years. Factory ammo. He liked my Win. 94 30-30 with 311291 175 grain load with 10 grains unique for about 1450 fps. My neck size only reloads would not chamber in his Marlin. He reloads cowboy ammo but this will be his first time loading 30-30. I told him about flaring the case neck for lead bullets.
So, which cast bullet might be his best choice for 100 yard plate shooting and reduced recoil like mine. And what sizing diameter?
Thanks ahead of time.

[Sam Sackett]

My 336 likes the Lyman 31141 sized at 309. Gas checked, powder coated and grease lube. Loaded on top of 29 grains of IMR 4895. On the road right now and don’t remember the OAL. If I remember right, I had to shorten it a tad to get it to work smoothly. Load one without crimp and try it in the gun. If action binds, shorten a bit and try again. You’ll find a sweet spot for your rifle.

Sam Sackett

[Texas by God]

I had good luck with the 170gr Lee sized .309” in a Glenfield 36G.


Sent from my iPhone using Tapatalk

[smkummer]

My 336 likes the Lyman 31141 sized at 309. Gas checked, powder coated and grease lube. Loaded on top of 29 grains of IMR 4895. On the road right now and don’t remember the OAL. If I remember right, I had to shorten it a tad to get it to work smoothly. Load one without crimp and try it in the gun. If action binds, shorten a bit and try again. You’ll find a sweet spot for your rifle.

Sam Sackett

I have that mold, but after you size it are you then powder coating it? That’s gonna add a bit of size to the bullet. At this point I may make him some sized to .309. These will be water hardened clip on wheel weight alloy at about 20 BHN hardness.

[trapper9260]

My 336 likes the Lyman 31141 sized at 309. Gas checked, powder coated and grease lube. Loaded on top of 29 grains of IMR 4895. On the road right now and don’t remember the OAL. If I remember right, I had to shorten it a tad to get it to work smoothly. Load one without crimp and try it in the gun. If action binds, shorten a bit and try again. You’ll find a sweet spot for your rifle.

Sam Sackett

I have that mold and size it to .310 and works for me .

[Tatume]

I had good luck with the 170gr Lee sized .309” in a Glenfield 36G.

This bullet is very accurate in my Microgroove JM Marlin 336.

[smkummer]

This bullet is very accurate in my Microgroove JM Marlin 336.
What diameter are you sizing to?

[Tatume]

I've tried 0.309", 0.310" and 0.311" and all were excellent. Use whatever you have, as long as the cartridge will chamber.

[missionary5155]

Good morning
Use a fired cartridge before resizing to discover what is the largest diameter cast to use. If a .312 or larger cast will slip fit into the fired brass you have a real good idea how to seal the throat area. Under size "pistons" never give the best use of expanding gasses.
If you have a "diameter pin set" this is a real simple procedure. If a .315 does not enter the fired brass go to the nest smaller diameter that does.

[trapper9260]

Good morning
Use a fired cartridge before resizing to discover what is the largest diameter cast to use. If a .312 or larger cast will slip fit into the fired brass you have a real good idea how to seal the throat area. Under size "pistons" never give the best use of expanding gasses.
If you have a "diameter pin set" this is a real simple procedure. If a .315 does not enter the fired brass go to the nest smaller diameter that does.

This is a good tip on use of a fired case to see about the bullet. Thanks

[RickinTN]

The Accuratemolds 31-180R is a bullet I designed for Marlin 30-30 microgroove rifles. It shoots very well. Order it with .311" diameter and .300" nose. It shoots quite well and it's not shabby in a 30-06 or even a .308 Winchester Remington 700 with their long throat. My favorite load is 15 or so grains of IMR4227. I haven't chronographed the load but probably between 1,400 and 1,500 fps. As mentioned above it is a good idea to use a fired case and use the largest bullet which will chamber. .310" works for most of my 336's.
Good Luck to you and if you don't have one Tom's molds are a work of art.
Take care,
Rick

[MostlyLeverGuns]

I like the RCBS 30-180-FN, I size at .310 for my Marlin 336 Microgroove and Ballard rifled leverguns, also works well in my Savage 99 .303's, .308's, and 300 Savage's. Usually use 5744 but have used 2015 and 2495 in the 30-30, I have also used 15grs IMR 4227 in the 30-30 with the RCBS 180 for excellent accuracy.

[FergusonTO35]

I had good luck with the 170gr Lee sized .309” in a Glenfield 36G.


Sent from my iPhone using Tapatalk

This, I size mine to .310.

[Sam Sackett]

I have that mold, but after you size it are you then powder coating it? That’s gonna add a bit of size to the bullet. At this point I may make him some sized to .309. These will be water hardened clip on wheel weight alloy at about 20 BHN hardness.

Yep. Final size to 309
Sam Sackett

[floydboy]

I shoot the same boolit, powder and grains as Sam Sackett. I size at .311.

Floyd

[smkummer]

Thanks everyone. I only have Lee bullet sizers so it’s .309 or .311. .311 works in my pre-64 94 Win.. I think I’ll start with .309 first for his gun and see how it works.

[imashooter2]

My microgroove 336 likes them hard and fat. I use a Lee C309-150-F water quenched and sized to .310.

[RickinTN]

If need be that Lee .309" sizer can be opened to .310" easy enough. I also think you can order a .310" direct from Lee but not sure about this.
Good Luck,
Rick

[smkummer]

Ok, update. He had a lot of fun shooting 311041 sized to about .310. We never put it on paper as he had too much fun shooting this discarded air tank at 100 yards. 10 grains unique.325505

[Texas by God]

Ok, update. He had a lot of fun shooting 311041 sized to about .310. We never put it on paper as he had too much fun shooting this discarded air tank at 100 yards. 10 grains unique.325505

I like it!
I call that “Scrapyard Prep”!


Sent from my iPhone using Tapatalk

[MarkP]

RCBS 30-150 Cowboy. Its a plain base design thaylt shoots well in my 30-30's both Winchesters and Marlins (micro grooves)

[smkummer]

I got him talked into Lee’s C309-170-F with Sage gas checks.

[smkummer]

So the above Lee 170 grain gas check mold seated where the crimping groove is located won’t chamber as the micro groove rifling is engaging the forward ogive of the bullet. Sure seems odd that a design for the 30-30 can’t be seated in the crimping groove where intended? Out of spec mold? I’ll tell him to call Lee and see what they say.

[Jeff Michel]

if you can find one, 311440.

https://www.accuratemolds.com/bullet_detail.php?bullet=31-150L

[imashooter2]

My C309-150-F engraves rifling too. The lever closes just fine and the boolits don’t pull if I want to unload it without firing.

[RickinTN]

Engaging the rifling is a good thing if it doesn't interfere with the bolt closing or removing a loaded round. It contributes to accuracy.
Good Luck,
Rick

[Griff]

So the above Lee 170 grain gas check mold seated where the crimping groove is located won’t chamber as the micro groove rifling is engaging the forward ogive of the bullet. Sure seems odd that a design for the 30-30 can’t be seated in the crimping groove where intended? Out of spec mold? I’ll tell him to call Lee and see what they say.

My C309-150-F engraves rifling too. The lever closes just fine and the boolits don’t pull if I want to unload it without firing.What length are you trimming your brass to? I trim all mine to 2.028" and have no issues feeding & chambering in multiple rifles. I even trim new brass as it is often inconsistent in length.

[ChuckJaxFL]

Engaging the rifling is a good thing if it doesn't interfere with the bolt closing or removing a loaded round. It contributes to accuracy.
Good Luck,
Rick

https://uploads.tapatalk-cdn.com/20240501/7f2ceda4335076bf1772c2e171b066c6.jpg
I just took possession of one of the new Ruger 336SBL’s. I’ve only had it to the range for one trip and have only tried a few starting loads. This is the NOE 312-151-RN, powder coated & sized to .311.

I can feel some slight resistance closing the lever, and quite a bit extracting the unfired round. I’ll try a few more traditionally lubed, and some with good old Alox. The first rounds showed promise, accuracy wise. But I’m concerned about chamber pressure. If other-than-powder coated bullets don’t chamber/extract easier, I’m going to abandon trying to pair this bullet with this rifle.


Sent from my iPhone using Tapatalk

[scattershot]

[ATTACH=CONFIG]326174[/ATTACH This is with the Hunter Supply 165 grain bullet, but there are molds available for it, too. Marlin 336, Micro Groove barrel.

Edit to add:
310 diameter

[RickinTN]

https://uploads.tapatalk-cdn.com/20240501/7f2ceda4335076bf1772c2e171b066c6.jpg
I just took possession of one of the new Ruger 336SBL’s. I’ve only had it to the range for one trip and have only tried a few starting loads. This is the NOE 312-151-RN, powder coated & sized to .311.

I can feel some slight resistance closing the lever, and quite a bit extracting the unfired round. I’ll try a few more traditionally lubed, and some with good old Alox. The first rounds showed promise, accuracy wise. But I’m concerned about chamber pressure. If other-than-powder coated bullets don’t chamber/extract easier, I’m going to abandon trying to pair this bullet with this rifle.


Sent from my iPhone using Tapatalk

I don't think there is any worry about chamber pressure from the engraving in your picture. Lead, even hard alloys are soft. If you were talking about then same situation with a jacketed bullet then there would probably be reason for concern but then again a jacketed bullet wouldn't chamber if it were the same diameter on the nose. Of course, as always, start with a reasonable powder charge and work up or down as indicated. In a 30-30 and a Marlin lever rifle if you actually see any traditional pressure signs you are well over the strength capabilities of the rifle.
Good Luck,
Rick

[Bazoo]

My friend's 336 does well with my handloads using the Lyman 31141 (https://bulletmatch.com/bullets/lyman-31141) sized to .310, lubed with White Label 50/50, and loaded at full pressure. We shot some on paper, and I don't remember specifically the group size, but it was acceptable and in line with the factory ammo we shot.

[10x]

I've tried 0.309", 0.310" and 0.311" and all were excellent. Use whatever you have, as long as the cartridge will chamber.

This ^^^^^^^ I have had several microgroove Marlins, They like 0.310" or 0.311" bullets,
Powder coated, gas check on, then sized to 310 or 311.

[davidheart]

My experience with the microgroove Marlin 336 is that both .309 and .311 sized boolits shoot acceptably. However, I had less leading with the 311 boolits. Likely because the width minimized blowby. The other thing I would recommend is to take a boolit or soft fishing weight and swage the barrel to find the actual groove diameter. Then go .001 over that.

[10x]

My experience with the microgroove Marlin 336 is that both .309 and .311 sized boolits shoot acceptably. However, I had less leading with the 311 boolits. Likely because the width minimized blowby. The other thing I would recommend is to take a boolit or soft fishing weight and swage the barrel to find the actual groove diameter. Then go .001 over that.

I have found that with Microgroove® 30 caliber barrels if a bullet that is 0.310" or 0.311" it will shoot more accurately than a smaller diameter bullet.
The 303 British with bore diameters of 0.314 have taught me that I should always be a minimum of 0.002" over bore diameter, and more diameter does not hurt unless the case neck is too large to chamber

My 9.3x57 has a very slender (tight) chamber neck and I have to reduce neck thickness to allow 0.368" bullets to seat without the neck being "sticky" Without thinning the neck i am limited to 0.367" max and slightly larger groups than the 0.368" sized bullet. 0.366" bullets that match bore diameter shoot a 2" group at 50 meters, 0.368" shoot a 1.25" group at 100 meters.
Years ago I read a statement by one of the pioneer cast bullet shooters - he wrote " the best cast bullet sizer is the throat of the rifle barrel." So far he has been right.
I have shot "as cast" powder coated bullets in my 303 MkIII martini that were 0.318" and they gave great groups. In the same gun 0.314" bullets would whiz down the range - spinning end for end and would key hole in a pattern at 50 meters.