Rebarrel a Marlin 1894 44 with syandard rifling?

[Shottist]

I have a Marlin 1894 44 Magnum carbine with a 20" Microgroove barrel that slugs 0.432" It won't shoot worth a hoot. Love the gun but hate the groups. At 25 yards from benchrest (peep rear sight) it goes 3" +/- with all loads. Read my Veral Smith book and then fire lapped the barrel with the NECO kit according to their instructions Tried the LBT 432-310 LFN bullet, the Ranch Dog 432-265 RF bullet, Sierra 210, 240 and 300 jacketed bullets just to see. Tried differebnt powders and velocity levels (chronographed all loads), still no better Best group at 25 yards was 2.5", worst is 3,5+", 10 shot groups. Numrich has a 20" 44 barrel blank that looks like it can be turned down to replace the Marlin factory barrel. Is there a better/cheaper/easier way to rebarrel this gun? Hate to get rid of it but want it to shoot 3 or 4 MOA groups. Since I shoot 1/4" groups at 100 yards with varmint rifles, I hope I am not the problem. Help!

[longbow]

I have a the same gun and it slugs 0.431"+ (maybe a little under 0.432" ~ tenths are a little elusive). I found tight spots in the barrel at dovetails per comments on the Marlin site so hand lapped them out. I know you fire lapped but you might just push a soft lead slug through the barrel to see if there are tight spots.

I also found that mine likes boolits at about 0.432" or better. I am using plain base boolits and unless they are large I get bad gas cutting with hot loads. Have you miked your boolits as cast or are you sizing and to what size?

So far the styles of boolits I have shot do not stabilize well at over about 265 gr. though other people have been getting good groups with heavier (longer boolits). Wide flat nose designs and Ranch Dog designs receive good comments. In any case, as long as it is sized appropriately (over groove diameter) I would figure the Ranch Dog 265 gr. would be a good performer.

Another thought ~ what alloy are you using? If you haven't been using water dropped wheelweights try that and if you have then maybe try oven heat treating to get then real hard.

And yet another thought ~ have you checked for leading? My groups were deteriorating before I lapped the barrel and though it wasn't obvious to look down the bore I had a very thin even layer of leading. It was likely due to the gas cutting. After I cleaned it out and lapped, then used 0.432"+ boolits performance was much improved.

Longbow

[Bret4207]

There are other places to look too. Is the buttstock really secure? Is the forearm binding? The sights loose? Barrel crown? Mag tube loose/tight/moving? Search the archives here and you'll find some good info. Marlins barrels usually are pretty good. Not being able to get groups with jacketed tells me it might be more than just the barrel not liking cast.

[Shottist]

I have re-crowned the muzzle at 11 degrees with the Brownell tools. The magazine tube and handguard are loose, per an old Gun Digest article on accurizing the Marlins. All sights & screws are tight. I use Hornady gas checks and size to 0.432 as measured with a dial caliper. Am using water-dropped wheelweights with 2% tin added from a bottom-pour furnace. Using LBT Blue lube, NRA alox/beeswax and tried other lubes-no difference. I keep the barrel clean with Ed's Red and/or Kroil. I will push a soft lead slug thru to check for tight spots-haven't done that yet. I have a Marlin 336 30-30 with microgroove barrel that shoots 2-3 MOA with the Lyman 170 flat point (#311041) bullet sized 0.310 at 2200 fps (with WC-844 powder) using the same bullet metal and casting technique. It also has an 11 degree muzzle crown and the loose magazine tube and forearm.

[Bullshop]

Try softer. just air cool and not quench. Air cooled ww at bhn 12 or so will handle any pressure a lever action can handle. Remember also its OK to clean a barrel but never run that first shot over clean dry steel. Its a good idea to pre-condition the barrel for the first shot. After that as long as your lube is working theres nothing to worry about.
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