Marlin 1894 44mag 5" groups, help

[lar45]

My brother in law came down to hunt pigs and brought his Marlin 44mag. We went to check the zero on the scope and it was all over the place. We checked the bases and rings, they we're tight. So we thought it must be a bad scope. We put on an old Simmons that came off my .308, but still the same. We went to town and bought a new one and now it started to group, but was giving 5" groups at 75yds.
His load is a Berry's 240 with 13.5 gns of Bluedot, I think.
We also tried some factory ammo with a bullet that looked the same, then some Remember 240 jsp. But they were all the same. We cleaned it, but no change. He says it shoots great with 180jhps.
Any ideas on what to check next?

[Silvercreek Farmer]

Reverify that it shoots the 180's well. Marlin 44s have slow twist barrels and will probably shoot lighter bullets better. Heavier bullets may work well if pushed hard with H110/296 or similar. Probably too hard for plated bullets. If shooting cast, the tend to need .432+ boolits.

[lar45]

We did get one last night, but he used his 7mag
243038

[lar45]

He didn't bring the 180s with him

[Larry Gibson]

lar45

Well cast 215 to 240 gr GC'd bullet sized .430 - .431 and lubed with BAC loaded over 17.5 gr Blue dot or 22 gr 2400 will probably shot as well as the 180s in that slower twist Marlin.

[TCFAN]

My Marlin 44 mag. would not group well until I went to .432 boolits and then tried .433 and that was even better and a gas check boolit improved it even more.I shoot the Lyman 429215 and Accurate 434230C all sized at .433.......

[osteodoc08]

My 1894 in 41 Mag took a while before finding a good load. It took a fatter, harder boolits with 4227 at moderate fast velocity. I haven’t chronoed the load yet but it was near the top end for 4227 loading which is slower velocity wise than 2400/296/LG.

[Norske]

My 1894 Marlin 44 mag has Ballard rifling, but it's not at all deep. My shallow-rifled Marlin shoots jacketed bullets much moer accurately than my cast (sized to fit my SBHs). The best load I've found so far is a 245 gr jacketed bullet and 20 gr Alliant 2400 and a Winchester large pistol primer.

[mattw]

Ditto, my 41 mag and 357 mag both want fatter boolits pushed fairly hard. I like H110 and 2400.

[Tripplebeards]

I’d try cleaning the barrel again a little harsher. Did you slug the bore? Maybe it’s a little larger diameter than spec? If not I’d call marlin, imo that’s not acceptable especially with j words. It would kinda make sense if the bore was larger than spec since fast, light 180 grain j words would expand to grab the rifling with a lot of speed and pressure...maybe I’m wrong.

[bmortell]

mine does good with .4325 diameter, quenched alloy, up to 300gr. mostly only shots good with h110, 4227 or 2400 roughly in that order, faster powders were hit or miss. i use plain base pc'd. I got to .75 at 25 with peep sights, it used to be twice as big as a minimum. check all other screws there everywhere. even things like the front sight screw might be loose even though your not using it, it might be shifting during firing.

[winelover]

+1 on the .432-433 bullets in Marlin 1894's.

243198

Winelover

[waco]

^^^I have to agree with John. A fatter .433" fixed my accuracy issues.^^^

[lar45]

I have the Lee 200gn mold and cast a bunch out of coww + tin and water dropped them. They came out at .430" , so I gave them a coat of Kawasaki Green and they were .4315" .
We loaded 10 each at 21 and 22 gns of 2400.
The 21 gn load was better than the Berry's 240s, the 22 gn load showed some promise.
Maybe with a little tweaking, or a different bullet I can get this thing to shoot.

243288

[knifemaker]

My grandson's Marlin 44mag. would not shoot good groups with .429-.430 dia. boolits. I now load a cast 250 gr. SWC boolit sized to .433 before I saw a great improvement in the groups. Most marlins run a .431 groove dia. and need larger dia. cast boolits to shoot good groups.

[longbow]

+ another on the fatter boolits!

I started out in ignorance of the fact that .44 mag rifles have larger groove diameter than handguns and Marlin rifles don't much like SWC boolits So I bought the very best highly recommended .44 mag. mould... the Lyman 429421.

Accuracy was at best mediocre and generally 4" groups at 50 yards and it leaded. It did better with "J" bullets but still not what I'd expect. Took me a while to find out that it likely had a large groove diameter so I slugged it and found it was 0.4315". My Lyman mould cast right at 0.429" with WW so undersize boolits! I might have added a thou or so with Lyman #2 alloy but still likely small so I made a mould to cast 0.432"+ and things improved. Then I tried paper patching and things improved some more. Then I got a Mihec mould that cast 0.434" and again accuracy improved. Fatter boolits = better accuracy for my gun.

Still got a bit of leading but not too bad.

The gun didn't like to feed the 429421 either since it is over factory OAL. I fixed that but that is another story.

Next I read on the Marlin owner's forum that at least some Marlins have tight spots in the barrel under roll stamping so I carefully slugged my bore and sure enough found tight spots. I decided I'd had enough so lapped the barrel by hand. This is a 1980's vintage microgroove barrel with 1:38" twist. I concentrated lapping at the tight spots then when they were gone I lapped a bit more at the breech end than muzzle end trying to put a very slight choke in the bore. Accuracy improved again and leading stopped.

Now it shoots acceptably for a lever gun.

Mine likes boolits of at least 0.433" and will chamber and shoot boolits of 0.435".

The gun has sat mostly unused for some time but I cast a bunch of boolits for it and will be taking it out for some exercise soon I hope.

Longbow

[lar45]

I gave some Lee 200s a double coat of powder coat to get .434" and will give them a try.
This rifle has the ballard rifling and slugs at either .431 or .432, I forgot, I'll have to measure again.

[Kev18]

I have one and use a 240grn SWC from hornady with h110. Mine is a newwer model made in 2011 though... And it doesn't have Ballard rifling.

[Greg G]

My 1894 does well with 240 jacketed as well as 250's I cast from an Accurate mold and size to .432".

A big problem with my gun was the magazine tube was binding against the bottom of the barrel close to the receiver. Once I relieved the barrel, the groups tightened up a lot.

[Walks]

My 1980's 1894 shoots well with a #429421 sized .430dia, same as I load for My .44Mags, Ruger's, S&W and for a short time a Colt. I have to feed them carefully with a slow easy LEVER and a bit of shake. The #429215 & 429244 feed just fine.

My "trick" to accuracy with my Old Marlin w/Micro-groove rifling and My other two. A Browning '92 from about 1982 and a 20" Winchester from 1987(Big 5 Special) is simple.

I put at least 1,000 Hot Jacketed loads through each Rifle and several 1,000 more cast of pure LINOTYPE.

My DAD said that was the same "trick" he used to get the U.S. M1917 Revolvers and G.I. barreled 1911's to shoot.

As CALIF has only allowed Jacketed Expanding Bullet's for "Big" Game since the 1960's. I burned up A LOT of Hot Loaded Hornady .44-265gr SP Hunting Hogs in Cenrtral CA.

Those will smooth out a bbl in a Hurry.

Don't really know why, but I got more .44's then any other caliber.

[missionary5155]

Good morning
Marlin rifles for too many years have been sold with fat throats and barrels. Ranch Dog Molds were designed to "fix" the issue.
Those originals have been copied by several mold makers that advertise here. Fat noses to fill the throat and fat diameters to keep the pressure to the rear of the lead slug piston. Large flats on the nose give good energy transfer on target.
Push them hard and fast and they normally will produce.

Especially in the Marlin 44 mag barrels you are faced with that slow twist. The faster you push the slug the more rotation speed is transferred to the bullet giving better stability down range. Happily the 41 mag has a 1-20 twist.
Mike in Peru

[17nut]

https://i.imgur.com/v92Q7oN.jpg
https://i.imgur.com/X2oMSw1.jpg

[Prairie Cowboy]

Yes, I just bought a .44 magnum 1894, and the barrel does slug out to .4315", which is pretty typical.
Marlin deliberately over-bores them to reduce chamber pressures. SAAMI spec for .44 marlin rifles allows a .432" bore.
My hand loads with .430" 240 grain Hornaday XTPs and 18.5 grains of 2400 produces a group of about 3 1/2" at 50 yards. I had read that Speer JSPs will "bump up" better than the XTPs and produce better accuracy.

A .433" cast bullet is what's needed, as long as the chamber will allow the fatter cartridge to chamber.

By comparison, my 1894 Cowboy in .45 Colt is able to produce 1" groups at 50 yards with open sights using standard low velocity American Eagle 225 grain JSP ammo.

[lar45]

I picked up some 240XTPs and with 20gn 2400 shot this group at 75 yds.
243962

[725]

For tight spots in a few barrels I've delt with, I've fire-lapped 'em with FLITZ and jacketed bullets.