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Microgroove Barrels

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01 March 2003, 02:57
sundog
Microgroove Barrels
Specifically a Marlin 336 in 35 Rem. I've never owned a microgroove barrel. I have heard pros and cons for a cast boolit shooter.

Any input? sundog
01 March 2003, 07:00
FAsmus
Sundog,

I do not have extensive expierience in Microgroove shooting, however, in the shooting I have done, with the 44 mag in a Marlin carbine I found that it worked quite well with "oversize" bullets.

I tried bullets sized to the typical 0.429/0.430 and had no accuracy. Then, since my old Lyman 429244 mold dropped bullets at 0.434 I hand lubed and loaded up a few as-cast and suddenly the gun's groups shrank down to a very acceptable level.

Good morning,
Forrest
01 March 2003, 07:53
z1r
I have two rifles with the microgrove barrels.

The .44 shoots well with .430" bullets the .30-30 uses .309" I've only shot the .30-30 once with cast so can't really attest to the accuracy yet.

The .44 however, shoots great. I find that moderately hard or harder alloys work fine.
01 March 2003, 08:18
Ed Barrett
I just picked up a Marlin this winter in 35 Rem. I haven't even picked up a set of dies yet. The bore is about perfect, so I'm going to try some cast loads. Will start out with some light semi-wadcutters because that is the only thing I have a .35 mold for.
01 March 2003, 09:38
graycg
I have a 357 mag Marlin with microgroove barrel, it shoots gaschecked 158 and 180 grain cast bullets very well at the 17-1800 fps level. I recommend that you slug your barrel carefull though, mine needs bullets at .360 to shoot well, 358s don't shoot well at all.
I've never had any leading and the gun shoots 3.5 inch groups with a Williams receiver sight at 100 yards. That's as good as it does with any jacketed bullets.

I think you can have a lot of fun with that gun!!

regards,
Graycg
01 March 2003, 09:47
Paul Brasky
Sundog, I have 2 Marlins wi. MG rifling, a .30-30 and a .45-70. Both shoot CB's as accurately as they do jacketed bullets. The problem, so to speak, isn't the type of rifling or the number of grooves, but finding a CB design and diameter that your bore "likes." Powder type and charge are important, but not as important as CB type and fit. Also, check the CB Board Archives for more on this subject. Hope this helps, ...Maven
02 March 2003, 09:38
JackM
Some Marlins in .35 Remington, including mine, have a very short throat and won't chamber a bullet that's over .356 ahead of the case mouth. Just load one, don't crimp it past straight, and try it before you load up a bunch.

Bye
Jack
02 March 2003, 12:22
Rrusse11
Sundog,
Take a look at the link here, then go to the left hand side, 3 lead boolit loads for the 35 Rem, gives various powders and group sizes acheived. Somewhere to start anyway. Your Mileage Will Vary I suspect, reading the above.

http://www.gmdr.com/lever/otrail.htm
02 March 2003, 12:31
DOUBLEJK
sundog
I load fer 2 of em. 1 mine the other is my Brother Inlaws. They shoot cast boolits real well.
For starters you might try about any .357 158gr. cast and 12-15gr. AA#5. Mine like em alot sized .359 so's it barely touches the boolit, I shoot em mostly fer plinkin'.
For huntin' I had Veral make a 235gr. LWFNGC and with enough H335 to get 1850fps it shot clean thru a broadside decent 5X5 Elk at 80yds. Only took the one, broke the near side shoulder and destroyed the lungs exiting the off side with a 1.5" hole. It work's on smaller big game just as well!! [Wink]
13 March 2003, 05:44
sundog
okay, fellers, thanks for the comments. Got the ole gal cleaned up and shot some over the weekend. Used some LBT 185 FN that Felix gave me to play around with in the Whelen. I loaded them over 38.0 WC844PD. Shot great and VERY clean. Just got a RCBS 35-200-FN and cast a few last night, and then checked and lubed them. I will shoot a few of them this evening. The only thing I've noticed so far is that the comb of the stock is a tad high for me - looks like I'll do a little woodworking to alleviate that problem, and all will be well. This is a 336CS, and so far I think I like it.