Marlin 336 and Lead Cast Bullets
- Thread starter WolfyW
- Start date
Admittedly, that's got alot to do with my query. Wondering about those microgrooves.
This is what is great about this forum. I went through this issue this past summer. It cost me two rifles and I learned a wealth of knowledge from others and about the Henry rifles as well. I now own a 2012 Marlin 336W and it is a fantastic lead shooter.
The very first thing to dispel is in regard to the micro-groove. It is an excellent rifling for lead.
The issue is that when loading the lead bullets, you need to expand the neck, exactly the same as you do with revolver or pistol loads. A fellow gun nutter explained this to me and he was spot on. I purchased the Lyman M-1 neck expander. This will work great for you.
Also the diameter of the lead bullet makes a difference too. I now use a bullet with .310 diameter with gas checks. Contact a fellow nutter (Barclay) as he will sell to you - they are great. The bullet barn are .309 diameter (165 gr) and work ok too, but they do not have gas checks and have to be held to a lighter velocity to minimize leading. I shoot mine out at about 1,200 to 1,600. I tend to have tighter groups with the .310 bullets.
Watch your powders. I use Unique, Trailboss, and RL-7. The Trailboss is a really light load and in most cases your real sight will not have enough elevation. I'm looking for a rear elevator sight to alleviate this.
Cheers!
The very first thing to dispel is in regard to the micro-groove. It is an excellent rifling for lead.
The issue is that when loading the lead bullets, you need to expand the neck, exactly the same as you do with revolver or pistol loads. A fellow gun nutter explained this to me and he was spot on. I purchased the Lyman M-1 neck expander. This will work great for you.
Also the diameter of the lead bullet makes a difference too. I now use a bullet with .310 diameter with gas checks. Contact a fellow nutter (Barclay) as he will sell to you - they are great. The bullet barn are .309 diameter (165 gr) and work ok too, but they do not have gas checks and have to be held to a lighter velocity to minimize leading. I shoot mine out at about 1,200 to 1,600. I tend to have tighter groups with the .310 bullets.
Watch your powders. I use Unique, Trailboss, and RL-7. The Trailboss is a really light load and in most cases your real sight will not have enough elevation. I'm looking for a rear elevator sight to alleviate this.
Cheers!
The one I loaded for was for the father in laws rifle, did not want him grumpy. He wanted around the yard coyote loads, used trailboss behind 100gr hornady half jackets I got at a gun show, worked great for him! Neck flaring and gas checks are a must on rifle rounds, for the time it takes to clean a leaded bore, gas checks are cheap even if you think your ok with your velocity and bullet size/hardness!!!
You will have to keep the velocity way down or the lead bullets will just slide through and lead up your barrel... the fine rifling is lousy with lead rounds... I would not bother.
Micro groove rifling is the worst for lead bullets compared to normal standard size cut rifling.
If you don't mind slow velocities you can shoot lead in any rifle.
Micro groove rifling is the worst for lead bullets compared to normal standard size cut rifling.
If you don't mind slow velocities you can shoot lead in any rifle.
That is not quite correct. The high velocities will cause the leading more aggressively. I have been shooting with gas checks and with rl-7, about 2,100 and 2,200 fps - no issues with leading and accurate as hell. Using Bullet Barn (no gas checks) I keep them down to about 1,500 fps and with trailboss I figure they be about 1,200 or so (10.1 grains), again, no leading. The microgooving in my Marlin shoots the leads out tighter than my Henry - with the standard rifling. That was why I ended up back with the Marlin - cause it shot so great.
One fantastic round I use is the RL-7 with the Hornady 100 grainers. they are very straight and hit with a bit of a punch too!
I was not referring to lead with copper gas checks... I was referring to my Browning 92 .44 Mag and 240 grain lead bullets... fast did not work, period. 700 f/s was fine.
The faster bullets (1000 f/s) skidded through the barrel because the microgroove rifling could turn the bullet as fast as the forward movement... Accuracy was lousy and the bore was leaded in a few shots.
...and I am still not talking about copper gas checked lead bullets.
You accuracy gain was probably because of a better quality barrel. Micro groove works well with copper.
The faster bullets (1000 f/s) skidded through the barrel because the microgroove rifling could turn the bullet as fast as the forward movement... Accuracy was lousy and the bore was leaded in a few shots.
...and I am still not talking about copper gas checked lead bullets.
You accuracy gain was probably because of a better quality barrel. Micro groove works well with copper.
the guys at castboolits.com would disagree with you and tell you to size the bullet properly.
what size cast bullets are you shooting in the microgroove?
did you slug the bore?
Undersize bullets are the problem. Hot gases from the chamber passing through the tiny bullet-bore gap act like plasma torches eroding lead from the bullet and depositing it on the bore.
The bullet (gas check or not) has to be sized a couple of thousands of an inch larger than the bore. For this you have to know the exact diameter of the bore. Easy to do by pushing a pure lead slug through the barrel and then measuring said slug (with a micrometer!).
You can find plenty of information at http://castboolits.gunloads.com/ even without registering.
Another good resource is http://www.lasc.us/Fryxell_Book_Contents.htm There you can even find a gas check vs plain base article.
Yes the whole slugging thing is a good idea, but as I found out, if you do not expand the neck, the result will be an undersized bullet from shaving. The bottom bullet was shot out of a Henry rifled barrel. I found it on the ground where it tumbled and skipped off the turf. The top bullet was a slugged through a Marlin barrel. Both are .309' in diameter. Both barrels were brand new. The bullet now shoots very well out of my Marlin 336W (micro-grooved barrel) now that I expand the neck size.
I now use a .310 (gas checked) bullet from a fellow gun nutter which shoots more accurately with the lighter load and heavier loads.
I now use a .310 (gas checked) bullet from a fellow gun nutter which shoots more accurately with the lighter load and heavier loads.
- Location
- Somewhere on the Hudson Bay Coast
In his book, "Jacketed Performance With Cast Bullets" Veral Smith opines that good success can be had with micro-groove barrels, and pointed out the accuracy of Marlin rimfires as evidence. Myself, I never had any success with lead in the 95 Marlin I had back in the '70s.
Northman999
CGN Ultra frequent flyer
- Location
- Southern Yukon
I haven't shot the 336, but my Rossi R92 in .454 Casull is micro groove.
It is fine with cast lead if you do one of two things.
1. Shoot softer lead FASTER NOT SLOWER, so it expands to fill the bore tightly. 800 - 1700 FPS works fine, no leading, and good accuracy. I'm doing this with Cactus Plains 250 gr FRP.
2. For harder bullets, size them larger. My rifle shoots hard cast .454 bullets much more accurately than hard cast .452. I've taken .460 cast bullets from 45-70 molds in the 340 - 350 grain range (Lee and Ranch Dog six cavity molds), and resized them to .454. Also cheaper than getting a custom "heavy" mold for the .454 or .45 colt, particularly if you already have 45-70 molds handy.
I did quite a bit of poking around on the internet to check out this whole "micro-groove can't shoot cast" thing and it seems that most of the time micro-grooves just need a bit more experimenting, and typically, bullets sized 1-2 thou larger is the solution.
It is fine with cast lead if you do one of two things.
1. Shoot softer lead FASTER NOT SLOWER, so it expands to fill the bore tightly. 800 - 1700 FPS works fine, no leading, and good accuracy. I'm doing this with Cactus Plains 250 gr FRP.
2. For harder bullets, size them larger. My rifle shoots hard cast .454 bullets much more accurately than hard cast .452. I've taken .460 cast bullets from 45-70 molds in the 340 - 350 grain range (Lee and Ranch Dog six cavity molds), and resized them to .454. Also cheaper than getting a custom "heavy" mold for the .454 or .45 colt, particularly if you already have 45-70 molds handy.
I did quite a bit of poking around on the internet to check out this whole "micro-groove can't shoot cast" thing and it seems that most of the time micro-grooves just need a bit more experimenting, and typically, bullets sized 1-2 thou larger is the solution.
