308 or 309 resizing die for 309 boolit?

[Lead Freak]

I'm buying a Lee 113gr or 150gr 309 dia boolit mold and I'm not sure which resizing die to go for. I will be loading 30-30 Win. for a Marlin micro-grooved lever gun and would like to know if I should go with a 308 or 309 resizing die. What are the pros/cons for each?

[Ben]

Possibly neither of the ones you've listed. Many Marlin Micro Groove rifles got their bad reputation for shooting cast bullets with the very diameters that you've listed.

When people began using a 310 and even better a .311 sizing die for their cast bullets, they found out that Marlin Micro groove barrels would really shoot well.

[Hurricane]

I think .311 would be a good choice. I use .311 for all 30 caliber uses.

[williamwaco]

I think .311 would be a good choice. I use .311 for all 30 caliber uses.





DITTO.

Rifles and handguns.

[6.5 mike]

When you get your sizer push a boolit through it & check the size. I have a number of them & all where smaller the claimed. It does let you "custom" fit them as you need.

[btroj]

It matters not what size the bullet or mould wants- it only matters what the barrel wants.

I size to .311 for my Marlin 30-30 with microgroove and get good results. .308 or .309 is likely to make the barrel very unhappy.

[cbrick]

When you get your sizer push a boolit through it & check the size. I have a number of them & all where smaller the claimed. It does let you "custom" fit them as you need.

In all probability what your measuring is the variation in alloy as sized differences. Most of my dies will size my alloy about .0004" smaller than die marked diameter except my four 30 caliber dies that size the same alloy as die marked diameter + .0001-2". Any change in your alloy will changed the as sized diameter.

Rick

[frkelly74]

+1 .311, Slug the bore and see what it measures.

[Idaho Sharpshooter]

I learned, in Schuetzen and CBA competition; a number of interesting things.

1. Everything you do to the cast boolet after the sprue solidifies is bad for it. The sizing die has a certain +/- manufacturing tolerance. So does the top punch. So does the sizer ram, and the machine itself. Scheutzen guys pan lube their boolets so nothing harder than the lube itself touches the boolet until it is breech seated. CBA guys generally size in a die slightly larger than the "As-Cast" dimension and then swage it to fit their custom chamber reamer throat. The two groups top shooters arrived at the same conclusion independently: fitting the throat is T-H-E most important of the accuracy equation.

Since the CBA records are in the .2 to .25 moa range, I have changed my boolet treatment to parallel theirs.

YMMV*

Rich

* Your Mileage May Vary

[HARRYMPOPE]

"Everything you do to the cast boolet after the sprue solidifies is bad for it

if done wrong yes.Like Rich says bumped or re-swaged bullets in good dies are as accurate in BR guns with fixed ammo(most CBA records are with bullets massaged as such).I cant argue with the Schuetzen guys as Tommy Mason And Bev Pinney have told me pan lubing in 32 Millers and 32-40's cant be beat and i believe them.Now breech seating and fixed ammo are different animals .

What CBA matches have you been attending Rich?

George

[mpmarty]

Forget sizing it just adds problems. Measure the as cast diameters and see if they will chamber. I let my barrels size my boolits.

[MtGun44]

308 will certainly be undersized, 309 almost certainly. By .310 you may succeed, but
Microgroove bbls are often oversized slightly. You need to slug your barrel, and size a bit
larger, like .002 at least more than the groove diameter. If you don't slug, start at .311
and see how it goes. mpmarty's idea is not a bad one.

Bill

[Maven]

LF, Perhaps my Marlin #336 (ca. 1991) was an anomaly, but it greatly preferred CB's sized to .310" over those sized to .309" or .311". Although Lee Precision doesn't currently offer .310" sizing dies, they do have a .309" die, which you can easily enlarge to .310" and then .311" if necessary. Here's how it's done: http://www.castpics.net/subsite2/HowTo/How%20to%20Hone%20a%20Size%20Die.pdf

[rond]

I use .309 in mine, but I use a gas check.

[Lead Freak]

308 will certainly be undersized, 309 almost certainly. By .310 you may succeed, but
Microgroove bbls are often oversized slightly. You need to slug your barrel, and size a bit
larger, like .002 at least more than the groove diameter. If you don't slug, start at .311
and see how it goes. mpmarty's idea is not a bad one.

Bill

Could I safely assume that if the bullet will chamber, that it will be safe to shoot (considering bullet diameter that is)? I guess what I'm worried about are higher pressures caused by a larger diameter. Should I start with a lighter charge when increasing bullet diameter?

[DLCTEX]

Marlin chambers are generally large. I don't recall ever hearing of one that would not accept a .311 boolit.

[1Shirt]

No question in my military mind on this one! Go with .311! The only thing that I have in 30 that shoots .308-309 is my K-31 Swiss which is that tight. .310's shoot ok in most of my 30's, but not as well as 311's, so the .310 sizing die seldom, if ever in the last few years gets used. Good luck!
1Shirt!:coffee:

[shootrj2003]

Why resize?why not just use a .311 bullet mold.i am asking because I want to cast for a 30/30,I was going to buy a .309 double cavity from Lee and now I hear people who should know telling me to buy SKS size cast bullets! I want to keep this simple( KISS) I have lots of lead,lots of powder,jacketeds are not as cheap or easy to get as they were,but molds are easy to find,so why can,'t this be simple?!why is feeding my Marlin complicated?can someone help me buy the right stuff?do they even make a .311 mold for a 30/30?why do they make a .309 mold then?I don't do much cast bullets can you tell?

[charlie b]

These are good questions. The problem is that not all barrels are made equal, and different alloys cast at different diameters. Sometimes even changing the mold temperature or melted lead temperature can change the cast bullet dia.

Rifle manufacturers use tooling that is worn in use. As it wears the dimensions of the barrel will change a little. Older rifles made with cut rifling were even more varied in mass production since each operator measured as they went. And, as the barrel is fired it starts to wear out, so if you have an older barrel it may require larger dia bullets.

Marlin came out with the microgroove for some reason. Maybe they thought it was a good idea at the time, but, it made shooting with cast different than with standard rifling. The shallower rifling does not 'grip' the lead as well so a properly fitted bullet is even more important.

Lee made .309 molds because the majority of rifles made had .308 groove diameters. So, you could use their bullets without sizing when using wheel weight lead. The problem is if you have a rifle with slightly oversize barrel then they are too small. That's why you see Lyman and others make the bullets .311 or bigger. Some of the military surplus barrels might even need .314 bullets.

This is not a difficult thing to get figured out, but, it does take more than just a pot to melt lead and a mold when you are dealing with some rifles.

You should also know that you may need to use lower velocities than when using jacketed bullets.

Many of us who cast do like the challenge of making our own bullets that will come close to or out perform commercial bullets. It is not easy and sometimes not cheap to get started.

Something you might want to consider is powder coating your bullets. It increases the diameter a little bit and makes a 'tougher' bullet that does not lead the barrel as easily.