Marlin microgroove rifling and cast bullets

[goon]

I have a chance to buy an old Marlin 336 30-30 with a straight stock. I like the way the rifle handles and feels compared to the pistol grip versions. It still has a solid feel but it also seems to handle faster than the other style.
The only thing is that it has microgroove rifling. I haven't ever heard any problems with this when regular jacketed bullets are used. I have read that it doesn't work well with cast bullets.
I was planning to try some of the ones that oregon trail makes if I buy a 30-30. Does anyone know anything about this?
Thank you.

 

[LHB1]

Quote: "I have read that it doesn't work well with cast bullets."

I read that too but my personal experience was otherwise. Owned a Marlin 1894 in .44 Mag with Microgroove barrel and it shot cast bullets with great accuracy and no leading. The .30-30 will generate higher velocities so your results might be different. Try it and let us know your results. Sometimes I wonder how many of the people who post that statement have really tried good hard, ALOX lubed cast bullets OR are just repeating something they read. Good luck.

Good shooting and be safe.
LB

 

[mustanger98]

My advise is to buy the gun regardless of of the microgroove barrel. I say this because, despite my liking for Winchesters, I still maintain that Marlin 336 .30-30 is a great rifle.

Now, as to cast bullets, I've always heard they're not good in a microgroove barrel because it'll lead up fast. However, I've also recently heard barrels lead up fast because the powder charge was too hot for the lead bullet. That's why they went to jacketed bullets when smokeless powders came out... the powder was too hot and ran faster than a lead bullet is generally capable of. The way I understand it, the hot gas generated by the burning powder will blow around the bullet (through the grooves) and melt lead into the grooves. If the charge weight was backed down or a different powder was used, it might not be a problem. Also, if a gas checked bullet was used. Just some things to think about and maybe try. Barrels can be cleaned and another combination tried. You don't really know till you do try.

 

[ClarkEMyers]

Microgroove rifling works just fine with cast bullets BUT not the same cast bullets.

Microgroove rifling works just fine with cast bullets BUT not necessarily the same cast bullets. Hence commercial cast bullets that work fine in other rifles may not be the best in Microgroove rifling. I can't speak to the Oregon Trail bullets mentioned. They may well do just fine.

By definition Microgroove has a bigger bore and smaller groove diameter. Fit the bullets and match the alloy hardness to the pressure/intended velocity and they do just fine. Remember that fitting the throat may be and often is the critical area more important than the bore.

Generally melting the cast bullet is not an issue - recover properly fitting bullets and look at the bases - including sprue mark for most molds (obviously not nose pour) - for signs of melting given the base is always exposed to the worst the propellant can do.

.30-30 is great cast bullet cartridge almost everywhere.

 

[MCgunner]

Microgroove rifling works just fine with cast bullets BUT not necessarily the same cast bullets. Hence commercial cast bullets that work fine in other rifles may not be the best in Microgroove rifling. I can't speak to the Oregon Trail bullets mentioned. They may well do just fine.

By definition Microgroove has a bigger bore and smaller groove diameter. Fit the bullets and match the alloy hardness to the pressure/intended velocity and they do just fine. Remember that fitting the throat may be and often is the critical area more important than the bore.

Generally melting the cast bullet is not an issue - recover properly fitting bullets and look at the bases - including sprue mark for most molds (obviously not nose pour) - for signs of melting given the base is always exposed to the worst the propellant can do.

.30-30 is great cast bullet cartridge almost everywhere.

Nobody uses gas checks? They work on my .357s! They enable a lot more velocity than a plain base bullet. Jacketed allows more, of course. I push a 158 grain SWC to nearly 1900 fps in my Rossi M92 lever carbine with no leading. It is a Lee gas check mold design. I cast 'em of wheel weights with a little tin added for hardness (from 50/50 solder).

 

[cracked butt]

Gas checks are your friend.

 

[LHB1]

I used crimp-on gas checks for my cast bullets for .308 and .30/06 from Saeco mold but have never needed them on pistol bullets. I shoot std base H&G cast bullets using ALOX lube at 1425 fps thru .44 Mag's with no problems or leading.

Good shooting and be safe.
LB

 

[tom barthel]

Marlin microgroove barrels

Mine shoots lead pretty good. My bullets are mostly .432 to .433. All are gas checked. People have said slightly oversize bullets work best. Something about gas seal.If you don't find an answer here, try the beartooth shooters forum site.

Good luck.

 

[BruceB]

Micro-Groove discussion

Go over to www.castboolits.gunloads.com and search for "microgroove", because there has been a great deal of discussion on the topic on that site for quite a while.

Many of the members there have reported success with cast bullets in such rifles, so don't worry about it too much!

Besides, if you're interested in bulletcasting, THAT is the place to be (along with THR, of course!!)

 

[perpster]

If I just want to shoot factory loads in a Marlin lever .357 (plinking, target, defense), is there any particular barrel type NOT to get? I want to buy their 18 or 20 inch version but am confused by the barreling options.