How much freebore in a 336?

[Captain*Kirk]

My son just picked up a NOS (never fired, in original box with hang tags and stickers still attached) mid-nineties Marlin 336CS in .35 Remington...a near twin of mine. Since .35Rem ammo is 'unobtainium' these days, I offered to load him up some handloads. I've been using the Sierra Pro Hunter 200 gr (#2800) in my latest handloads, so I loaded up a dummy round with this bullet to check freebore and he closed the bolt on it. Seating the bullet with the bolt (zero freebore) puts the case mouth very near the upper edge of the cannelure, and is even less than the Sierra COAL recommendations of 2.475". How much freebore is the norm for this rifle? Just as a comparison, I also tried the same dummy round in my 336 and it checked zero freebore at the BOTTOM edge of the cannelure...quite a difference at 2.500". I'm wondering if he should maybe go to a different bullet profile, as in a Speer 180 or 220 grain bullet that might give a little more freebore to work with at recommended COAL settings? I'm wondering if factory ammo (provided he could find any) such as Remington 200gr Core-Lokt, or Winchester or Federal 200gr RN would even chamber in this rifle...?
FWIW, I have a half box of the Speer 220s and have loaded up a dummy round with this bullet for him to try.

[Nobade]

Normally none, the rifling just has a bevel on it right in front of the chamber with no parallel at all. Can't have much sticking out of the case or it won't work.

[earlmck]

Like Nobade says, the slightly irritating characteristic of the standard 35 Remington chamber is the barely more than "zero" throat (or freebore as you are calling it) area of the chamber, and it sounds like your son's new baby is even at the short end of this "almost zero" area. Jacketed bullets made for the 35 Remington are built for this, with the nose area all bore diameter. The 205 grain boolit molds from Lyman, RCBS, Lee etc. that are intended for 35 Remington are also designed this way. But not the heavier boolits as far as I know.

Some folks wanting to shoot a wider profile of boolit have gone to the trouble of reaming a more normal length throat into their 35 Remington chamber. I haven't done that myself but I did acquire a levergun so chambered.

[Captain*Kirk]

OK, sounds like what you're saying is (Reader's Digest abridged version) if I can crimp within the cannelure (even right up to the top edge) and the bolt will close on the cartridge then that's adequate with this cartridge?

[rond]

I trim my cases a little shorter for my Marlins.

[Tom Myers]

I used the Precision Cast Bullet Design ~ Ultimate (https://www.tmtpages.com/#ultimate) software to create this scaled image of my Marlin 336 RC with the dimensions of an impact impression of the chamber, a fired Privi PPU case and an N.O.E. 311041 Cast Bullet.
As you can see from this image and from all of the Marlin and Winchester chambers that I have worked with. the chamber is cut to the old original length of 2.1".
This leaves quite a bit of free space in the chamber before the begining of the throat and abrupt slope down to the groove diameter.
So, as long as the nose diameter is not over 0.300", most bullets with a reasonable driving band length, loaded in the usual 30-30 case lengths of around 2.03" will chamber in Marlin 30-30 chambers.

Hope this helps.

http://www.tmtpages.com/LinkSkyImages/30-30_Winchester_Marlin_93~Barrel~500-pi_Lg_30-30_Winchester_PRIVI~500-pi_N.O.E._Bullet_Moulds_311-184-FN_GC_J5_~500-pi_Lg.Jpg

[earlmck]

OK, sounds like what you're saying is (Reader's Digest abridged version) if I can crimp within the cannelure (even right up to the top edge) and the bolt will close on the cartridge then that's adequate with this cartridge?

Yep -- that's what I meant to say.

[Nobade]

I used the Precision Cast Bullet Design ~ Ultimate (https://www.tmtpages.com/#ultimate) software to create this scaled image of my Marlin 336 RC with the dimensions of an impact impression of the chamber, a fired Privi PPU case and an N.O.E. 311041 Cast Bullet.
As you can see from this image and from all of the Marlin and Winchester chambers that I have worked with. the chamber is cut to the old original length of 2.1".
This leaves quite a bit of free space in the chamber before the begining of the throat and abrupt slope down to the groove diameter.
So, as long as the nose diameter is not over 0.300", most bullets with a reasonable driving band length, loaded in the usual 30-30 case lengths of around 2.03" will chamber in Marlin 30-30 chambers.

Except the OP was asking about a 35 remington 336...

[ulav8r]

Snip
So, as long as the nose diameter is not over 0.300", most bullets with a reasonable driving band length, loaded in the usual 30-30 case lengths of around 2.03" will chamber in Marlin 30-30 chambers.

Hope this helps.

snip


When I first loaded cast for my Marlin Glenfield 30-30, the loaded cartridge was hard to chamber and when ejected showed about .10 inch of rifling engraving on the bullet. Was using the Lee 150 grn flatnose bullet with the case crimped into the bullet cannelure. Do not remember the COAL, it was in 1974 and all my loading notes are packed away since my last move.

Had the rifle throated so that issue was no longer a problem.

[Tom Myers]

Except the OP was asking about a 35 remington 336...


Opps!! I really stepped in it that time.
I suppose that, because I like my Marlin so much, all I saw was the "Marlin 336" and just carried merrily along from there.

[yeahbub]

Having looked into this sort of thing in the past, I learned that lever action chambers usually have no true throat like in a bolt-action, aside from the Browning BLR's which are lever operated bolt-actions chambered for ammo that was designed for turn-bolt rifles. The usual practice is a chamfer from chamber neck diameter into the rifling at 45 deg or less. A bit of wear (or pressure-lapping) can give the impression of having a throat when using bore-riding cast boolit designs, but in store-bought jacketed lever gun ammo, the bullet ogive starts at the case mouth. That the rifle is new would explain why the seat-to-touch exercise you mentioned puts the case mouth at the forward edge of the cannelure, indicating a properly dimensioned, unworn chamber. I'd bet that a couple hundred rounds from now, this same exercise will result in a bullet seated with more of the cannelure exposed.

[Captain*Kirk]

Some great replies here! I loaded him up a pair of dummy rounds; one with the Sierra 200 grain RN and one with the Speer 220gr (both loaded long) and told him to chamber both. We'll start out using the one with the most cannelure showing ...and maybe after a couple hundred rounds we can check to see if the throat has broken in. I will also try trimming the brass back to max trim length and see it that makes a difference?
Thanks for all the help, and I'll keep this thread updated!