what feed and what shoots...marlin 1/138 micro groove

[mike in co]

ok....various comercial jacket bullets fit and function, but of the cast....what is strange is the 280 lbt wfn(?) functions no problem, while more conventional swc 255 will not.
i plan on starting wth the pb lbt with the same load i currently use in my 7.5 SRH.
IT RUNS ABOUT 1050 WITH 17.X OF WC820 WITH FELIX LUBE.
will i run out of lube in a 20" bbl ? water quenched ww sized 4316.
the 280 is .750 long...someone said .7 is max for 1/38.....
will try the gas checked 290 group buy when it is delivered too(.80 long).
wonder what happens if i hollow point these two ?
what else might work ?

thanks
mike

[Bass Ackward]

Will i run out of lube in a 20" bbl ?
Wonder what happens if i hollow point these two ?
what else might work ?

thanks
mike


Mike,

I shot a 280 LBT with GC for almost a decade. You have plenty of lube carrying capibility if it is good enough or slipery enough. Depends on how smooth your bore is really.

Pretty simple really. From my experience, if you get improvement hollow pointing, then you have a stabilization problem. If you don't have a problem, then it won't make any difference accuracy wise.

What else might work? I shot 20.5 grains of H-110 for years.

[mike in co]

ok have heard of issues with micro groove ......
i got boolits to fill the bore, but have one more question.....

do gc boolits perform better in the micro groove or is it really just fit ??

thanks
mike
44 mag 280/290 boolits

[9.3X62AL]

Mike--

How does the boolit in question shake out when Greenhill Formula is applied?

[longbow]

Mike:

I have been wondering the same thing and have asked various people and gotten various responses. Most seem to figure that at least up to 300 gr. boolits work well in the 1:38 Marlin if they are pushed out fast.

Not so with mine. I have been testing accuracy at various ranges with boolits from 220 gr. to 300 gr. - standard cast with lube grooves, smooth with no lube grooves and paper patched. So far the indications for my gun are that around 270 gr. at about .72" is the max weight/length it will stabilize. This is in agreement with Greenhills.

I have tested: a round nose flat point with small meplat and get good accuracy up to 265 gr. or so.; Lyman 429421 which does not feed well even crimped over the front driving band to get overall length right and groups mediocre at all ranges and all loads (I don't like it at all); paper patched truncated cone which shot well at weights to about 250 gr. and stabilized 300 gr. to about 75 yards then keyholed at 100; 300 gr. jacketed which were literally all over the countryside at 50 yards.

All cast boolits have been plain base but leading is not generally a problem.

Powders so far are H110, IMR 4227, Unique and Blue Dot. Obviously best velocities are with H110 & IMR 4227.

The only load I remember for sure is 21 gr. H110 with 300 gr. paper patched - flattened primers. The other I would have to look up. Too many loads, too small a brain!

My conclusion so far is that for my gun which is 0.4315" groove shooting a 0.432 or larger boolit around 270 gr. is the max weight/length for accuracy past 100 yards. At 50 most any of the loads are okay and some very good.

I have not tried any of the 300 gr. WNFP or Ranch Dog boolits but read on this site that many have good success with them. I like the Ranch Dog 265 gr. (or is it 285 gr.?) and may see if I can get hold of a mould or at least boolits to test. Possibly you can get a selection of boolits to try and then buy a mould for what works best.

Currently I am working on some penetration tests for varying weights of same design boolits from 240 to 300 gr.. Kinda looking for optimum weight/penetration. If the heavier boolits (300 gr.+) significantly out perform the lighter (265 gr.-) then I may look at rebarreling or simply buying a newer Marlin with faster twist.

The standard semi wadcutter design is not in the plan though.

I hope that helps.

Longbow

[Bass Ackward]

ok have heard of issues with micro groove ......
i got boolits to fill the bore, but have one more question.....

do gc boolits perform better in the micro groove or is it really just fit ??

thanks
mike
44 mag 280/290 boolits

Mike,

Do GCs perform better? Yes .... and No. My most accurate load to date is with a PB just saundering along about 1250 fps. Push it faster and it just becomes another good bullet.

Longbow,

Good work and a nice write up. But I have one suggestion about :

<<Currently I am working on some penetration tests for varying weights of same design boolits from 240 to 300 gr.. Kinda looking for optimum weight/penetration. If the heavier boolits (300 gr.+) significantly out perform the lighter (265 gr.-) then I may look at rebarreling or simply buying a newer Marlin with faster twist.>>

Stabilization is often thought of in terms of air only. Stabilization is a factor that goes until velocity drops slow enough that it is lost. This counts in flesh as well.

Remember your range testing. The best way to see stabilized penetration is to see what penetration looks like at the max range you intend to hunt. One bullet may slow down more than the others and while it wins the testing up close, it fails to penetrate farther out.

That's why I always say test at the maximum range you intend to shoot at game.

[Glen]

I've gotten fine accuracy with 300 grain cast bullets out of my Marlin 1894 .44 Magnum. For details, go to:

http://www.leverguns.com/articles/fryxell/marlin_1894.htm

[mtngunr]

I've gotten fine accuracy with 300 grain cast bullets out of my Marlin 1894 .44 Magnum. For details, go to:

http://www.leverguns.com/articles/fryxell/marlin_1894.htm

Glen, as much as I enjoy reading your stuff on the internet, from the old sixguns/sixgunner days, all the way up to the leverguns stuff, and most importantly, the bookmarked and often read/referenced lasc site, it would really, REALLY be helpful and entertaining if you had a nice old fashioned book that I could buy and read even when the power goes off or the internet is a long gone defunkt nightmare that the grandkids giggle about when it is mentioned......such a book would get a lot of use, and be a most welcome and important addition to any cast shooter's library..............HINT..................

[Glen]

Well mtngunr, thanks for the sentiments, that book is almost done. The writing is pretty much wrapped up and I'm working on the photography and trying to find a publisher willing to print the thing.

[mtngunr]

Excellent news!......Don't thank me for wanting a good reference book....and it would be good....most definitely inform here, leverguns, sixshooter, etc when you get the details nailed down, as you surely will sell at least one.......quite a few more than one, in all probability.......

[Newtire]

ok....various comercial jacket bullets fit and function, but of the cast....what is strange is the 280 lbt wfn(?) functions no problem, while more conventional swc 255 will not.
i plan on starting wth the pb lbt with the same load i currently use in my 7.5 SRH.
IT RUNS ABOUT 1050 WITH 17.X OF WC820 WITH FELIX LUBE.
will i run out of lube in a 20" bbl ? water quenched ww sized 4316.
the 280 is .750 long...someone said .7 is max for 1/38.....
will try the gas checked 290 group buy when it is delivered too(.80 long).
wonder what happens if i hollow point these two ?
what else might work ?

thanks
mike


Hi Mike,
Just so happens I have done a heap of shooting with my Marlin .444 with the 1/38 twist and micro-groove. Send me your E-mail address & I will send you the loads I have so far. I shoot the Lee 200 gr. RN FP plainbase, Lee 215 gr. SWC Plainbase, the Lyman 429244, the Lee 300 grain, and lately the group buy RanchDog 277 gr. (weight out of my mould). Seat the Lyman over the top band and use 23 gr. Alliant 2400 or 20.5 gr. BlueDot. The Lee 200 gr.and 215 works best with 12 gr. Unique or 13-14 gr. BlueDot. It's getting late and have to hit the hay but will send you a Word Doc. with the details if you want to try some loads in that thing that really work well.