Marlin 336 30-30 reloading need help!

[slips73]

Ok so i got a problem approximately 50% of the rounds i make wont fit in my chamber, I am going to do this via pictures i took so bear with me. (PS: I am using a lee loader)

1st step. )

I take my deprimed and cleaned brass and prime it and resize the case mouth. It looks like this, neck sizes and all the brass cycles fine through the rifle.



Step 2.) This is were i ran into problems originally, I wasnt think and wasnt belling the case mouth for my cast bullets so the neck was bulging, ok those i separated (about 4) So after finding my case mouth widening tool I widen them like this. (yah im probably widening to much and will wear out the mouth but its all i got right now.)




Next step.) Now that it is no longer shaving lead I proceed to load powder charge and seat bullet.
My problem arises when the bullet is seated, if it looks like the first picture it usually works and seats in the chamber ok.



BUT if it looks like this it will not work and gets stuck midway into the chamber.



and this is as far as the lever goes.




continued....

[slips73]

There is something i noticed though, some of them if i try again will work but they come out with what i believe is rifling imprints on the bullet like the picture below, this lead me to theory B, described below, and no i dont have many tools to size bullets I bought these (250) of midwayusa.




So here is where i am at. two theories.

A.) The crimps are too hard on some and bulge behind the bullet making it unchamberable. ( I have about 13 like that wont chamber)
-the problem with this is some of them when measured have no crimp and dont chamber where as one has a crimp and will chamber.

B.) and i think this is more probable, the bullets are .311 diameter, now I always heard that marlins w/ microgroove have a larger chamber so i went with the .311 bullets over .309, is this my problem? If so why do some of them fit (roughly 15 of them fit fine)
-I am thinking that the bullet being to large, expands the brass neck on my already assumed tight chamber and it wont chamber or it wont seat in the chamber because the bullet di. is too large.

i am quite stuck as you can tell. any help is appreciated, thanks

-Adam


I also checked OAL between a cartridge that fits and doesnt fit, both 2.49" and rest of specs line up or just under factory specs. ASIDE FROM bullet diameter...is this my issue?

[sparky45]

Did you check the brass length? Maybe they need to be trimmed.

[slips73]

Did you check the brass length? Maybe they need to be trimmed.

Posted this a few different forums and general consensus seems to be the bullets are the problem. .311 diameter along with the shape.

[btroj]

Your crimp is excessive. It can bulge the neck below the crimp leading to difficult, or impossible, clambering.

Try a round with no crimp or just enough o remove the expansion of the mouth create dr o ease seating. It that round chambers then you know the answer.

The bullet can touch the lands and still function. If it is lightly engraved and the lever closes with a reasonable effort then load and shoot away. If the engraving is enough to make closing the lever difficult I would try a different alloy that could cast a tiny bit smaller or change bullets.

First issue is to identify exactly what your problem is. One thing I use at times is to color the neck and bullet of a loaded round with a Sharpie marker. It helps show exactly where contact is occurring.

[Win94ae]

B.) and i think this is more probable, the bullets are .311 diameter, now I always heard that marlins w/ microgroove have a larger chamber so i went with the .311 bullets over .309, is this my problem? If so why do some of them fit (roughly 15 of them fit fine)

That is the problem. I suspect some do chamber because the quality control of those bullets aren't up to par.

But...
Your bell is way too much, as well as your crimp. I bell mine so slightly that I can't tell it is belled with my naked eye. With the crimp, I barely notice there is one.

I use the Lee 150gr FN (Lee C309-150-F) which is the same shape as that bullet; it works wonderfully!

[sparky45]

What did the bore slug out to be? My 336 slugged at .309 on the button. I routinely use .311 cast without any problems. I do use a Lee FCD and just snug the case mouth closed. I'm thinking now (since you already checked the case length) that the shape of the cast bullet is the problem.

[Win94ae]

Not to say that your cases could be in needing of the shoulder bumped back some. But the bullets are a problem, which is in need of addressing.

[Bullshop Junior]

The bullet is hitting rifling for sure. Wondering is fine half of them
Chamber and half don't....is it a two cavity mold? Possible that one cavity is a little
Larger then the other.

[Bullshop Junior]

The bullet is hitting rifling for sure. Wondering is fine half of them
Chamber and half don't....is it a two cavity mold? Possible that one cavity is a little
Larger then the other.

[YunGun]

As you mentioned, many people (including myself) find better results with wider bullets in the microgroove barrels; mine definitely prefers .311 over .309. Because most sizing dies are spec'd for jacketed bullets, they will typically resize the neck to ~.307 which will make for a tight fit with .311 dia. bullets & can lead to the neck bulges you mentioned when seating or crimping (HIGHLY recommend a Lyman "M" Neck expanding die), but I'm not convinced that's whats preventing those rounds from chambering.

I can't really make out any difference between the third picture (round that chambers) & the fourth picture (round that doesn't chamber); they both look pretty good to me. However, I can tell you that your picture of the lever shows it in almost the exact same position that I encounter stiffness in closing the lever due to my boolits engraving into the rifling. Since my cast boolits for this rifle are pretty hard it takes a fair amount of force to close the lever & engrave the nose into the rifling, but results in some pretty darn good accuracy so I deal with it.

The last picture isn't the clearest but it certainly does appear to show signs of engraving from the rifling, which isn't really a problem & many even find desirable, although this can definitely lead to stiff closing of the lever. Since these are commercially bought cast bullets I'd bet they're pretty hard which may contribute to the difficulty.

Try taking one of your rounds that won't chamber & blacken it with a sharpie, then try chambering it again & check to see if any of the black is scratched off on the brass, indicating that the case wasn't fully resized. If that doesn't seem to be the issue try seating the bullet just a little bit deeper in one of the problem rounds, then see if it will chamber more easily. You might also just try cranking down on the lever on one that's difficult to chamber & see if it really is just biting into the rifling as I suspect; If that's the case (& you consider it a problem), likely your only options will be to change to a narrower bullet nose profile or seat them deeper than the crimp groove.

[Echd]

I sometimes use the expander ball from my 7.62x39 dies on fatter bullets in my .30-30. If you have the option also try sizing to .310.

I have had good results in different guns ranging from 309 to 311, but I have been told marlins enjoy fatter pills, esp. if microgroove.

[rintinglen]

I had the same problem with my 30-30's and the Lee Loader. It is very difficult to crimp consistently when you are pounding on a holder with a hammer. Do yourself a favor and spend about 60 bucks. Right now Midway has Lee die sets for 30-30 on sale 27.99, including shell holder and factory crimp die. Order a set and the Lee Hand press, or their single stage press. Either will run you about 30 bucks. The FCD will eliminate your crimping problems. The press will eliminate the banging. You'll be glad you did.

[btroj]

Guys, sizing diameter isn't the reason the NOSE is engraving the rifling. The nose is far smaller than even .309. The nose is more likely .301 or smaller.

The body diameter is NOT the same as the nose diameter on a bore ride bullet like shown.

Nose size dies do exist or can be made, these let you make the nose diameter fit your bore.

[Garyshome]

Did you check COL? Might be a bit long?

[btroj]

Too long total cartridge length wouldn't lead to this problem, in a Marlin it would cause the bullet nose to hang up between the magazine and chamber and wedge there. That assumes it wasn't too long to get out of the magazine fully.

[sparkz]

What is your OAL loaded?
What is the Brass trimmed to?
do you Chamfer the brass to help the boolit NOT shear off?
your really opening up that bell on brass and them crimping crazy hard IMO,,
I size to 309, but just got a 310, so il try to see what I have,,
your loaded shell looks to long to me, rifle imprints a lot!

I have and load for a 336 and have not had those issues I use a lyman book for specs and stick to them

Hope some of this helps you

Patrick

[sparky45]

Respectfully btroj; the Nose of the cast bullet ISN'T engraving on the rifling, it's way behind the Nose and within a mm of the rim(ridge) of the crimp groove. At least that's what it looks like to me. Are the cast bullets concentric?

[RickinTN]

Respectfully btroj; the Nose of the cast bullet ISN'T engraving on the rifling, it's way behind the Nose and within a mm of the rim(ridge) of the crimp groove. At least that's what it looks like to me. Are the cast bullets concentric?

Anything in front of the front driving band of the bullet is the "nose", and the nose is engraving the rifling. Marlins have little to no throat. My bet is that there is excessive crimp which is bulging the case mouth just behind the crimp and the diameter of the loaded round is larger than the throat on the rifle. The engraving of the nose will cause some resistance but can also lead to excellent accuracy.
Rick

[btroj]

Ok, the portion forward of the front driving band is the nose of the bullet. This is a bore riding nose, it is designed to ride on top of the lands, hence the name.
The portion of the bullet forward of driving bands, or fully diameter body, is considered the nose of the bullet.

This area is NOT sized by any normal sizing device. In general this part of the bullet has a diameter determined only by the dimensions of the mould and the alloy used.