cast .30 projectiles

Moderators:gds, bakerjw, Dolomite_Supafly

Post Reply
irondog808
New Member
Posts:2
Joined:Sat Nov 21, 2020 8:30 pm
cast .30 projectiles

Post by irondog808 » Thu Aug 12, 2021 2:50 am

hi guys , i have these HRBC .30 projectiles and i havent reloaded cast before , should these be loaded with gas checks ? see link link below for bullet info etc..

https://www.deltamike.co.nz/product/hrb ... ojectiles/

gun is a bolt action howa mini action chambered in 300 blk , 12.5" barrel , i dont know if i can shoot these
suppressed or not (if anyone has a recipe please add ) otherwise i will just be loading with ADI 2205 which is equivalent to H4227 / H110 , W296 , A1680

cheers

BulletFlight for Android
BJK
Silent But Deadly
Posts:207
Joined:Thu Jun 18, 2020 8:30 am

Re: cast .30 projectiles

Post by BJK » Thu Aug 12, 2021 10:56 pm

I wish more was told about the lube. Basically "dry lube" is meaningless. More info would be helpful.

I would ask them what the lube actually is. If it's a polymer coating it can mean that those bullets can be driven quite fast with few considerations. But I'm a noob to casting and that was told to me when I asked. I ask lots of questions. As far as a GC, load and see. My moulds allow for a GC but I won't put one on unless it's needed. I was told that a GC might result in better accuracy. There's only one way to find out.

cdl
Senior Silent Operator
Posts:106
Joined:Thu Sep 15, 2016 2:30 am

Re: cast .30 projectiles

Post by cdl » Tue Aug 17, 2021 1:00 am

The rule of thumb for cast is 120,000 to 140,000 RPM max. I think that Howa is 1-7 twist. So, that's 1167 fps to 1361 fps. Those bullets are pretty hard so you can probably push faster, but would want to keep an eye on what's happening. A 165gr bullet at that velocity is kind of like a Lamborghini on a city street but I'm sure it would be fun. Even more fun in a 1-11 twist like a 308 Win though. With a 308 you could wind it out...

Looks like those bullets are cut for a gas check so they should be more accurate with one. I've shot thousands and thousands of cast 237gr NOE at subsonic velocities in a 1-7 and 1-5 twist. Powder coated, gas checked and suppressed. Only reason to shoot a sub is if it's suppressed :lol:. The gas checks made a noticeable improvement in accuracy over the plain base mold I started with.

I went through a phase where I was using special plain base gas checks on plain base cast bullets and they would end up on the ground out in front of the suppressor. That's why I bought the gas checked molds. The standard gas checks seem to hang on to those just fine. I've never seen one come off, but even if they did, my suppressor has blown hundreds of the plain base version right out the front and onto the ground (snow). No problem, no sweat, no fear. Course that's me, not you, so I can't recommend it.

irondog808
New Member
Posts:2
Joined:Sat Nov 21, 2020 8:30 pm

Re: cast .30 projectiles

Post by irondog808 » Sat Aug 28, 2021 10:57 pm

cheers for the replys , another problem i have run into was these HRBC bullets measure out at .309"
i have jacketed one's that measure out at .308 and are easy to seat and chamber perfectly , on the 1st cast bullet i tried in one of my case's it wanted shave the side so i got a neck flaring die and slightly flared the neck , this made the bullet seat better but i had issues trying to chamber it , the necks in my brass are all in the range of .011 - .012 so are in the OK range , ive weeded out any cases that were up in the .014 / .015 size , what im asking is should i
run these through a LEE .308 bullet sizing kit and throw a gas check on while im doing it ? ..but when i look up the kit
on the LEE website there is this message at the bottom " For cast bullets, you want to select a sizing kit to be .001" larger than groove diameter." so do they mean use the .309 kit ?

i am using a factory crimp die and once crimped measures out at .335
my jacketed reloads measure .330

User avatar
dellet
Silent But Deadly
Posts:6640
Joined:Fri Nov 30, 2012 1:25 pm

Re: cast .30 projectiles

Post by dellet » Sun Aug 29, 2021 9:45 am

irondog808 wrote:
Sat Aug 28, 2021 10:57 pm
cheers for the replys , another problem i have run into was these HRBC bullets measure out at .309"
i have jacketed one's that measure out at .308 and are easy to seat and chamber perfectly , on the 1st cast bullet i tried in one of my case's it wanted shave the side so i got a neck flaring die and slightly flared the neck , this made the bullet seat better but i had issues trying to chamber it , the necks in my brass are all in the range of .011 - .012 so are in the OK range , ive weeded out any cases that were up in the .014 / .015 size , what im asking is should i
run these through a LEE .308 bullet sizing kit and throw a gas check on while im doing it ? ..but when i look up the kit
on the LEE website there is this message at the bottom " For cast bullets, you want to select a sizing kit to be .001" larger than groove diameter." so do they mean use the .309 kit ?

i am using a factory crimp die and once crimped measures out at .335
my jacketed reloads measure .330
I would leave the bullet size alone and check your math and measurements.
If the loaded diameter is .335” , that can cause chambering problems. If the bullet is .309, then the case wall is .013”. Your chamber might be on the tight side, .335” is minimum spec for the neck area.

Make sure that you check all the way to the base of the neck, there can be a taper. If it’s converted brass it will be more likely to be thicker at the base.

Since your jacketed bullets only measure .330”, it sounds like something is going wrong when seating the cast and they are not straight. I don’t know why else a .001” difference in bullet diameter would result in a .005” difference in loaded diameter. Reducing the bullet diameter to .308” won’t likely correct the oversize issue if it is a seating problem.
300 Blackout, not just for sub-sonics.

Post Reply