Info on cast bullets

[lechwe]

OK. I've been handloading for decades but have always loaded copper jacketed or solid jackets. With all the craziness out there I found some coated cast bullets for my 10mm. I've never loaded this type of bullet before and see people talking about sizing them. Do I need to get a sizing die and run them through before loading them or am I good to go? They are supposed to be .401. Just want to be sure before I go to work.

Thanks

D

[The_Shadow]

Hello and welcome to the forum lechwe!  They are probably already sized properly at 0.401".  You will want to fully seat them without any crimp being applied, that will prevent any snagging or shaving of the coatings (same for lead alloy without coatings).  The afterwards you can go back and apply a taper crimp to finish.  Measure the crimp on the very edge of the case mouth and it should be about 0.4220" - 0.4215".  Do not use the LEE factory crimp die because it can squeeze the bullet smaller that it is.
I use a 1/8" spacer under my seater/crimp die to raise it up enough that the crimp doesn't occur. (using that spacer means I don't have to adjust my locking ring each time)
After all of my cartridges have the bullets seated I take the spacer out and back off the bullet seater to final crimp and finish.

[Kenk]

Welcome lechwe!

[lechwe]

Hello and welcome to the forum lechwe!  They are probably already sized properly at 0.401".  You will want to fully seat them without any crimp being applied, that will prevent any snagging or shaving of the coatings (same for lead alloy without coatings).  The afterwards you can go back and apply a taper crimp to finish.  Measure the crimp on the very edge of the case mouth and it should be about 0.4220" - 0.4215".  Do not use the LEE factory crimp die because it can squeeze the bullet smaller that it is.
I use a 1/8" spacer under my seater/crimp die to raise it up enough that the crimp doesn't occur. (using that spacer means I don't have to adjust my locking ring each time)
After all of my cartridges have the bullets seated I take the spacer out and back off the bullet seater to final crimp and finish.

Thank you. I've got a set of RCBS dies with a taper crimp die. I'll seat them and then go back and crimp them. That is once I find primers. I have 3k large pistol primers but picked up 250 once fired brass and they are all small pistol primers. Didn't realize they made them with both sizes. A bit frustrating for sure.

[sqlbullet]

Great info provided, I want to add some ugly wrinkles to this.  Hopefully this will not be information you need, but it might.

First, you will need to take some care to remove all copper fouling from a barrel before you switch to lead.  Lead loves to stick to copper and will do so readily if you shoot lead bullets in a barrel with copper fouling.  Grab a bottle of good copper fouling remover and run patches until they come out clean.

Second, while .401" is the "nominal" size you need, the actual size can only be determined by measuring the groove diameter on your gun(s).  This is known as "slugging the bore" and is accomplished by driving a soft lead slug, usually a lead fishing weight, through the barrel and then measuring it with calipers.  Most 10mm barrels will slug between .399" and .400", but some (looking at you Glock) will measure over .401".  The bullet size you actually need for ideal results is observed groove diameter + .001".  For most 10mm guns a .401" nominal size meets or exceeds this requirement, but for some guns it does not.

So, what happens of your gun measures .4015" and you shoot .401" bullets?  Leading...Lots of it.  And harder bullets will make it worse, not better.

Think of this like a plasma torch, which is actually exactly what it is.  If you take the gas from a plasma torch and output it onto a steel base from a .400" nozzle, it is not concentrated enough to cut/melt the steel.  This is what happens in your chamber/barrel when you have good bullet fit.  But, if the bullet doesn't fit well and seal the bore, then plasma escapes around the sides of the bullet, essentially creating a very concentrated plasma nozzle.  This will cut/melt a channel in the side of the lead bullet and the cut/melted lead will get deposited on your barrel.

Most of the time bullets sized .401" work fine.  But unfortunately if .401" bullets don't work, the problem is almost always bullet size, not bullet hardness.  In fact, a soft bullet can be "bumped up" in diameter a tiny bit to seal the bore (see obturate).  It is a bit counter intuitive, but if you encounter leading, faster (more pressure) may be better than slower (less pressure and obturation), and softer may be better than harder if you can't control the size.

Good luck, and welcome to a whole new addiction.

[lechwe]

sqlbullet, Unfortunately I haven't dropped the hammer on a live round with this new gun yet. I'll keep all of this in mind. Right now I only have 200 rounds of factory ammo right now and until I can either find brass that takes large primers or I find some small primers I'm not loading any of my cast bullets yet.

Thanks for all the info guys. My first 10mm and 1911 so I'm having fun even if I haven't puled the trigger yet.

[sqlbullet]

Best of luck.

I was going to say I could bring you some primers in October when I visit your great state, but then I realized I won't be checking a bag and I can't carry anything you need on the plane.  Hopefully by then the shortages will have ended.

[lechwe]

Best of luck.

I was going to say I could bring you some primers in October when I visit your great state, but then I realized I won't be checking a bag and I can't carry anything you need on the plane.  Hopefully by then the shortages will have ended.

I just appreciate the thought!! Thank You!

I was told small rifle primers could be substituted for small pistol. Is this true?

[blaster]

I am almost out of small pistol primers but have a LOT of small rifle primers. recently I did an experiment with loading up a bunch of 9mm ammo with sm. rifle primers. I shot them out of 5 different 9mm hand guns. (2 were striker fired) all pistols shot every round on the first strike. I wasn't able to compare the rifle primed with the pistol primed ammo on the chronograph but I felt no difference in recoil or noise. if sm. rifle primers were ALL I had, I would not hesitate to use them.