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View Full Version : What hardness should I be using for .300blk subsonic 230gr?



Pyrex
09-29-2014, 04:08 PM
Anyone in here cast using the lee 230gr mold? What hardness are you using? I'm coating my bullets with hi-tek, and I'm curious if I'm too soft. Velocity will be 1050-1,100.

dtknowles
09-29-2014, 04:37 PM
I don't see how you could be too soft unless you are using absolutely pure lead. I would think 9 BHN would be just right.

Tim

JSnover
09-29-2014, 05:34 PM
I'd worry about sizing first. More than one member has shot cast at much higher velocities with no gas checks and no leading. Hardness won't save you if your boolit is undersized.

Hardcast416taylor
09-29-2014, 08:33 PM
Straight wheel weights or a 50/50 alloy of Pb/WW is about you`ll need. If you feel you need a harder bullet, water drop them for surface hardening.Robert

Pyrex
09-29-2014, 08:56 PM
Straight wheel weights or a 50/50 alloy of Pb/WW is about you`ll need. If you feel you need a harder bullet, water drop them for surface hardening.Robert

Well, I was careless with a few ingots, and I can't recall if they are COWW or SOWW's. I don't have a hardness checker, so i'm somewhere between 6-12. I do water drop all my projectiles, but if it's SOWW, the antimony percentage is so slim, I don't think it's going to do anything.

cbrick
09-29-2014, 11:45 PM
The key to your answer lies in the title to this thread . . . "Subsonic".

Cast what you have and try them, odds are good they will be fine.

Rick

Pyrex
09-29-2014, 11:51 PM
The key to your answer lies in the title to this thread . . . "Subsonic".

Cast what you have and try them, odds are good they will be fine.

Rick

My concern is I'm firing them out of an m16 on full auto, so the barrel is going to heat up quickly. I'm not sure if hardness plays a role in leading with that.

geargnasher
09-29-2014, 11:53 PM
I posted recently in another thread about shooting the NOE 247 subsonic in a .30-30, those bullets come out about 9 bhn and are absolutely fantastic shooters in the quiet velocity range. The only issue I could see is the noses getting dinged badly or peeling shavings off and hanging up when feeding if you have the M4 feed ramps and/or some very sharp edges in the chamber entrance or chamber/throat transition. If you have issues with that, you might consider water-quenching right out of the mould to harden them a bit, but they will likely require a different powder to shoot well than the softer ones will.

Gear

cbrick
09-30-2014, 12:54 AM
I have no experience with loading for full auto but as Gear said, if it feeds and chambers well you should be ok. The only other thing that comes to mind at the moment would be lube if the barrel gets really heated.

Where it me I would shoot some to what happens. Report back with your findings, I'm sure there will be others will be interested in the results.

Rick

dtknowles
09-30-2014, 12:58 AM
Less tin and antimony means higher melting point so softer could be better.

Tim

runfiverun
09-30-2014, 01:04 PM
I'm using the watever's in the pot that makes them 310 on that base band or so and air cooling.
if the bases are well filled out and sharp they shoot a lot better..

my objective is a lot different than yours though, I'm at the slow quiet one at a time end of the spectrum.
I got other molds to work on the 1300+ scale end of things.

Pyrex
09-30-2014, 02:47 PM
I'm using the watever's in the pot that makes them 310 on that base band or so and air cooling.
if the bases are well filled out and sharp they shoot a lot better..

my objective is a lot different than yours though, I'm at the slow quiet one at a time end of the spectrum.
I got other molds to work on the 1300+ scale end of things.

I assume you're shooting suppressed. Are you coating as well? Seen any lead buildup in your can?

runfiverun
09-30-2014, 06:13 PM
don't have the can yet, so I'm just working on the velocity, accuracy, and quietness of the load to begin with.
I have a bolt gun so I'm not limited with my load selection.
the issue I have right now is that as soon as I get quiet, I also get vertical stringing, so there is a definite line there.
3.5 grs of powder doesn't have enough muzzle pressure to cause any kind of gas cutting in that area, so I doubt any leading in the can could occur there without it being present in the whole barrel.

geargnasher
09-30-2014, 06:39 PM
Run, are you shooting the Lee bullet? TnT lube might help if the stringing isn't powder related. My Savage 219s wear 24" barrels, sound like a one-pump Daisy pellet rifle. No can required.

Gear

Pyrex
09-30-2014, 07:22 PM
don't have the can yet, so I'm just working on the velocity, accuracy, and quietness of the load to begin with.
I have a bolt gun so I'm not limited with my load selection.
the issue I have right now is that as soon as I get quiet, I also get vertical stringing, so there is a definite line there.
3.5 grs of powder doesn't have enough muzzle pressure to cause any kind of gas cutting in that area, so I doubt any leading in the can could occur there without it being present in the whole barrel.

I run 11.5gr of AA1680 for my subsonic, good case fillout, cycles very well and chronos about 1050. That load isn't going to be good for anything but a really short barrel though. I cut my barrel on a 1:8 twist blank to 6", so it's pretty short.


https://www.youtube.com/watch?v=0M6ibP_k6pc

This is with jacketed, but the same load.


Here's the first cast round I'm going to try.

http://i.imgur.com/c8eQHqt.jpg

Quiettime
09-30-2014, 08:54 PM
Gear beat me to it. Gotta cast hard enough for the autoloader. I use straight coww and working ok for me if I'm careful with magazine selection.

Quiettime
09-30-2014, 08:57 PM
I polished my feedramps a little with a dremel and it helped

Pyrex
09-30-2014, 10:50 PM
Gear beat me to it. Gotta cast hard enough for the autoloader. I use straight coww and working ok for me if I'm careful with magazine selection.

What COL are you running? I'm loading them long, the ogive looks quite sudden, but I chambered a few and i got one or two knicks, but none on the bearing surfaces, so I'm hoping it will be okay.

runfiverun
10-01-2014, 12:21 AM
yeah the lee t/l boolit, I'm still using up one of the test batches of 45/45/10 lube with wax and extra M/S.
I'm just searching that quiet/slow area for a cheap-o 50 yd shooter round that can be popped off all afternoon [cheaply] for some trigger time for the kids.

the vertical stringing in this case is being caused by the colder pistol primers I tried in this last batch, it doesn't do it with sr primers.
you'd think 3.5 grs of 700-x would be a pretty benign load, but it's just borderline enough to show up any inconsistency's.
I have some sp mag primers i'll give a go here soon, and see what they do.

Quiettime
10-01-2014, 08:38 PM
What COL are you running? I'm loading them long, the ogive looks quite sudden, but I chambered a few and i got one or two knicks, but none on the bearing surfaces, so I'm hoping it will be okay.

I'm actually using the NOE 247 and crimping in the groove. Bought a Lee 230 but it looked like **** out of the box and I didn't and I endied up not using it

Pyrex
10-01-2014, 09:44 PM
I'm actually using the NOE 247 and crimping in the groove. Bought a Lee 230 but it looked like **** out of the box and I didn't and I endied up not using it

Yeah I had burrs around the bearings. Not the prettiest die, but I drops okay, have to pop it open rather violently to get a clean drop, but it works. If I can get it shooting decent and this turns out to be a solution for me I'll have a custom mold made without any lube grooves.

dh2
10-02-2014, 02:48 AM
I am using 100% COWW having no problem with it

Pyrex
10-02-2014, 02:14 PM
I am using 100% COWW having no problem with it

What are you sizing to? My mold drops a .310-.311, and I'm resizing to .309 to start, see how that does.

Pyrex
10-04-2014, 05:17 PM
well, rather disappointing trip today. I was getting keyholing (as in 90* to target) at about 20-30 FEET. So definitely having some stability problems. I'm guessing 1:8 twist isn't enough on a 6" barrel to stabilize. Looks like I will have to go to a 1:7 to get these 230gr to fly right.

runfiverun
10-04-2014, 06:39 PM
that or speed them up a little.
I use thinner brass [prograde] that just allows me to get a 310 boolit in the case and chamber it.
I save the thicker 223 brass for 308 projectiles.
the LEE boolit is tapered from the drive band forward [mine is anyway] allowing me to move the boolit in and out of the case if I single shoot them.
the length is just right if I seat out to my longer bolt guns magazine, instead of the normal oal for an AR magazine.
I know this isn't much help but the brass thickness to your chambers diameter might help alleviate or point you to your issue.

MGnoob
10-04-2014, 07:34 PM
My concern is I'm firing them out of an m16 on full auto, so the barrel is going to heat up quickly. I'm not sure if hardness plays a role in leading with that.

They're not in the barrel long enough to matter, i guess unless you have a round chambered and not firing....and even then it won't matter

i found it interesting in my full auto tests that if a particular loaded projectile had an imperfect drive-band/base you could feel it when firing due to a slight interupsion in the consistency of cycle speed...I really enjoy when i fire it and it's a total consistent sewing machine. it puts an even bigger smile on my face knowing i have achieved "perfection" whilst reloading..

Now with the little subsonic experience i have, IMO it's ideal to have the alloy as soft as possible, it is where i found my best accuracy.
As you increase in speed(supersonic) you may need a slightly harder alloy or different bullet profile to prevent "nose slumping"

*edit* speeding them up may help, but if your goal is sub-sonic you may not be able to go faster
Also they need to be hard enough or seated deaper to withstand there trip from magize ,feedramp,chambering.
If the projectile gets bent they can jam..usually they'll still chamber and fire but makes for inconstancy in accurcy

243winxb
10-05-2014, 12:37 PM
http://www.bergerbullets.com/twist-rate-calculator/ Fine the twist rate needed. Harder alloy is needed. High rate of twist with soft alloy may let the bullet strip the rifling.

Pyrex
10-06-2014, 03:14 PM
http://www.bergerbullets.com/twist-rate-calculator/ Fine the twist rate needed. Harder alloy is needed. High rate of twist with soft alloy may let the bullet strip the rifling.

That calculator is showing my barrel has plenty of twist, but it also has no provision for barrel length. However the industry as a whole switching to a faster twist of 1:7 in short barrels, which leads me to believe it may be barrel. I ran a .309 and a .311 bullet and noticed no difference in the stability. About 80% were stable, 20% were badly keyholing. Maybe the hardness is the issue as you said... but many have said they are running a 5 or 6 brinell and had no issues. I wonder if it may be barrel length combined with this. I think I'll pickup a 1:7 twist 7.5" barrel and see how it does.

runfiverun
10-06-2014, 07:01 PM
try the harder boolits first.
they are trying to move forward, the rifling is trying to twist them.
you don't have a lot of distance to get them to do both.
if you have any slippage or any leading you will destroy either the diameter of the next one, make it harder to grip the rifling where the leading is, or just plain out not stabilize the slipping [skidding] ones.