Recently picked up  marlin 1894 (1977 date of manufacture) with micro groove.
Would one avoid cast bullets altogether?  Any accuracy issues?  
If cast is okay, any issues feeding SWC profiled bullets

thanks

If not shooting SASS/CASS matches, why not load plated rounds to be safe?  Hard cast lead is fine, but accuracy may suffer without diligent cleaning.

Round nose and round nose flat point are the safest in a lever gun mag tube.

my marlin 336 did not like lead bullets

I had one and you had to use oversized cast lead bullet to get it to shoot with lead.  I used .431 44 mag bullets.  .430 in jacketed.

Most people don't have a clue what they are talking about.  Lead works fine in microgroove barrels providing the bullets are oversized .001-.002".  They also need to be of adequate hardness for a given velocity.  As for profile you will have to try SWCs to see if your gun will handle them, my rifles feed them just fine.

Micro groove barrels can be a little finicky with cast but you should be able to get it to shoot reasonably well with them.

thanks for input.  I'll check for accuracy and leading issues and adjust accordingly.

Get .432 Dia from LazerCast.

or

Smasher from Missouri Bullet, Largest dia available.

Supposedly, leading happens more from underzised bullets vs. "too soft" bullets.

YMMV..

( FWIW, I just loaded 200ct of 180 JHP, for better accuracy and to avoid leading...)

Good luck!

FWIW,

My Marlin 1894, ca. 1998 does NOT feed 240g SWC's!

"Smasher" RNFP from Missouri Bullets are 100% GTG...

(Visit their site for more info...)

But, I'm getting away from them in my Marlin.

My Winchester, on the other hand, WILL feed:

240 SWC

240 TC

240 Smasher (240 RNFP)

Use about 0.001" oversize hard-cast. You will not have a problem; the problems associated with Microgroove rifling are vastly overblown.

I shoot SASS all the time with my micro groove Marlin 1894 in .357 Mag/.38 Special.  At those ranges....I see no down side.  Course, if you reload you could always play with bullet sizes and bullet hardness (speaking of lead bullets).  As for the SWC bullets.....yes, there are times that it'll hang up.  I've switched to the TC shaped 147 gr lead bullets and it's smoooooth.

158 gr RNL also works, but don't tell anyone.  Cause normally, they (RN) are not recommended in a tube magazine.

Some reading for you...........

http://www.lasc.us/FryxellMarlin-MicroGroove.htm

Aloha, Mark

PS.....Currently, I'm loading my SASS ammo using .38 Special brass, 147 gr TC lead bullets, 3.0 grn of Bulls Eye and at a COAL of 1.50".  Yes, COAL does make a difference.  You might want to play with your COAL to get things levering smoother.

I have an 1894S in 44 Mag. I shoot hard cast leads through it. It shoots them fine. I just give the bore a good leaning afterwards.