I have a 336 35 Remington with the micro-groove barrel. I’m going to run some 200 grain Cast Performance Bullets that are WLNGC. They are a brinell hardness 18-21. How fast can I push these bullets with the micro-groove?

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Man do some research on cast boolets.com I always heard micro grove and lead is bad juju

I know those bullets are hard and gas checked, I’d run it and see what ya get might clean it a few time to see just how bad it leads up if it even does.. I bet that gas check takes care of it tho..

2000-2200 I bet if the lead is that hard. Also depends on the pressure curve (what powder and load).

No idea yet. I have 3031 and a couple of other useable powders.

Following this because I have just started shooting cast bullets but I now have a question, do you still need to lube GC bullets, especially if they are over 1800 fps?

Toss all your lube and go the powder coating route...thankfully, I got into casting post-the lubing days and never had to deal with lube.

But I seem to recall folks have problems with coatings at speeds around 2,000 FPS? I understand the allure for pistol bullets.

First and foremost will be the bullet diameter, it should at a minimum be .001 over bore most go .002 - .003 over bore size. Gas checked bullets can be fired at jacketed bullet speeds, although I would stay mid-range on the jacket bullet speeds.

I've never had a single issue with powder coating at any speed with pistol or rifle, so I have nothing that I can contribute on that topic... it could just be I'm to ignorant to notice there is an issue - but my cast bullets reach the desired velocity and accuracy levels that I am after with no noticeable issues for a person of my skills level (which is to say, not an expert!). Mind you I currently only cast for:


Pistols
9MM
.40 S&W

Rifles
6.5 CM
30-30
300 Blackout
308 WIN
.50 Muzzleloader

Shotguns
12 GA. - Slugs only

One of the great advantages of jacketed bullets is that so many things do not have to be just right to get decent results. Cast bullets in rifle cartridges are very sensitive to the smoothness of your bore, diameter of your bore, alloy of the bullet, lube on the bullet and the gas check. The hardness of the bullet is important but not in the sense that harder is better. You certainly want the bullet to be over bore diameter but that assumes you know your actual bore diameter. But you also want to drive the bullet hard enough for it to obturate in the more. That gives you a better seal, less leading and more accuracy.... all things being equal. Cast Performance bullets are pretty hard and take a lot of pressure to obturate in the barrel. If you were trying to run loads much slower you would probably need a softer bullet. This is harder to achieve in a micro groove barrel but hardly impossible. Generally you want to run with appropriate powders on the slower side.

Do your research and see what happens with velocity, accuray and bore leading as you develop loads. Remember that you have to clean all the bullet lube out of the bore to see how much leading has actually stuck in the more. A little bit of leading is not a big deal. When you are done you will have given yourself a good education in high speed lead bullets.

My 336RC waffle top is thankfully too old to have micro-grooving. I use a Ranch Dog Lee bullet designed for my Marlin. It's PC'd and GC'd and is loaded over IMR3031 as well (I have reduced loads using A2400 and Unique as well). Only difference is it's a .30-30WIN not 35Rem. Don't need to lube them, that's what the PC is for. Big Sam has good advice there.



And BEFORE I started powder coating (previous owner of the mold made the notes on the box).

Thanks for your input GG. I have many thousands of rounds experience with coated handgun bullets but zero in a high powered rifle. I think the coating is more forgiving in handgun application vs lube. Would you say the same is true at rifle velocities????

I haven't tested much. Just started coating. Seems it's a win-win to me. Read this topic posted yesterday elsewhere about cast and coating .30-06 rounds.

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