Leading issues with cast .303 british

Tinman204

Tinman204

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This week I've been working on loads in .303 British for my Ross MkIII.

These are my first cast rounds so I was very anxious to load some up and shoot them! My load was 13 grains of red dot pushing a lee 312-185 gas check bullet with out a gas check with CCI 200 large rifle primers. I seated them out to the rifling minus .010". I lubed them with lee liquid alox lube.

After shooting a dozen or so I realized accuracy was none existent @ 50 yards! I inspected the barrel and found REALLY bad leading and the brass was black with fowling. I cleaned the bore and truer increasing the charge in 1/4 grain increments to try and get more pressure, it was worse on all of those loads.

I'll add that this gun shoots 2 moa with factory ammo or better with no issues with preassure, fouling or anything like that. The bore is like a mirror and I figured it would be a good candidate for cast loads.

Last night I slugged the bore and figured out that my barrel is .310. My bullets are casting at .3105-.311. I'm guessing that the bullets are to small causing gasses to slip by eroding the bullets and cause low velocity, bad accuracy and bad leading.

So here's my question, how should I go about increasing the size of my mould to try and get the bullets to drop at .313 or larger? Or am I missing something? The bullets seem nice and hard and were cast from wheel weights.

I know shooting cast is an art and a science and I really didn't expect great results to start off with!

Any tips from some of you more experienced guys would be great!!

Thanks, Steve.
 
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What velocity where you pushing the rounds and what kind of lead alloy where you using? Did you water drop or air cool? By black brass I assume you mean the outside was black?
Are you expanding the case necks? Even if the bullets aren't being shaved by the case neck they still may be swagged down by entering a tight case neck.
I've never had luck with loads that had pressure so low the cases had significant amounts of carbon on the outside. How much of which powder are you using?
Bullets dropping .3105-.311 out of a Lee mould designed for .312 sounds off to me. Most of the time with wheel weights and water dropped my bullets drop .0015-.003" larger than rated (.003" increase is only in 45 cal or larger).
Why no gas checks? The rebated rim at the bottom designed for the gas check can increase pressure around the base which may be causing the leading. Generally with cast bullets you always want full bore at the base whether it's lead or a gas check.
It may sound like a dumb question but how are you lubing your bullets? Are you following the tumble lubing instructions provided by Lee? I only ask because I talked to one guy that would put lube down on wax paper and just touch the bases of each bullet into the lube. No lube was entering the lube grooves so he was essentially firing unlubed bullets.

Simply casting larger bullets may not be the solution to your problem. I am dealing with this in an 1894 Marlin in 44 mag right now. The bore slugs .433" but even with .435" bullets I am having terrible leading. I loaded up a lot more varied loads to see if pressure makes a difference. Also from my experience so far casting for 7 different rifles, what may have solved a problem in one rifle might not have any effect in another.
 
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To answer your questions LUTNIT:

My charge was 13 grains of red dot and I worked up to 14 grains.
I tumble lubed the bullets as per Lee's instructions, letting them dry for a couple days on wax paper.
I dropped the freshly cast bullets onto a wet towel.
I'm flairing the cases by "bumping them with an 8mm sizing die. I've noticed zero shaving of lead off the bullet after seating.
I didn't use gas checks as they are sold out everywhere locally and I'm going to order some.
Not sure about velocity and pressure as I'm doing the "Harris load" which is said to be low pressure and a velocity in the 1200-1400 fps range and most say I shouldn't need gas checks at that speed.
My alloy was straight wheel weights that were sorted to insure no other material was added.

I also shot some of these loads out of my no4 mk1 lee Enfield with an AG Parker target barrel. Thought I'd see if it was just my Ross not liking something. It slugs identical to my Ross and had the same problems with fouling and zero accuracy. My Enfield shoots 1 1/2 moa or better and my Ross is a 2 moa gun no matter what.

I also tried some .323 bullets cast at the same time and shot them out of my Mauser. All 3 had the same leading and Terrible accuracy. I expected this from my Mauser as the barrel is frosted and slugs a little on the large side.

But my Ross and enfold have mirror smooth bores that are in amazing shape.

So should I drop the bullets directly into water? Is this why they are cooling and shrinking? Also more lube/less lube my be the problem? I shouldn't need gas checks at this low of a charge but maybe that's the problem. It seems like low pressure is what's giving me trouble.

I'll add that these are my first attempt at casting lead bullets, read and re read the instructions for lubing and cast to make sure I didn't do things wrong, but maybe I did?

At the end of the day it seems like the common denominator is the bullets. They cast well and most are shiney and weren't cast too hot. There's lots of lube in the grooves but still lots of leading. It just seems when I'm shooting that there's a good amount of the gas blasting out of the barrel, which is why I'm pretty sure that the bullets aren't obturating properly and therefore I'm having low pressure and leading.

That my take on things but if I had the answer I clearly wouldnt be posting here!:)
 
I can't remember the name of it but if you put a thin layer of tape on your mold blocks it will produce bigger bullets. I've never tried it as it seems like it would make fins and through off the concentricity/roundness of the bullet.
 
What you describe is a good method for loading cast bullets. There doesn't seem to be anything wrong with your technique as far as I can tell. I haven't used much Reddot in rifle cartridges as it is rarely recommended on any places I have looked. Personally I have the best results with H4895, SR-4759, Trail Boss, and Unique.

Water dropping bullets hardens them with the rapid cooling (but they soften again over time) and the extra size is from the tin content from what I've read (it expands slightly while cooling). Pure lead water dropped softens back to pure lead after only a couple days I believe. Lead alloys containing tin and antimony don't soften for a couple to a few weeks depending on composition. Even when softened lead alloy is still harder than pure lead.

What is your source of lead? I've never shot pure lead through anything but a shotgun before but harder lead alloys (I use wheel weights) are recommended for anything but black powder loads. Bagged lead shot is usually a pretty hard alloy.
I'm not sure if the lack of a gas check is the cause of the leading or not as I've never fired bullets designed for a gas check without one. Over on the cast boolit forums they say to always use a gas check if your bullet is designed for one. I order aluminum gas checks by the 500 off of eBay for cheaper than any local store carries them. I've had no difference in performance after switching from copper Hornady gas checks to eBay aluminum gas checks. Personally I would try gas checked bullets before I tried larger bullets since size shouldn't be an issue with the barrels slugging under bullet size.

As for too much or too little lube that shouldn't be an issue. A very thin coating of liquid alox is required for proper lube and if you add too much it usually gets scraped off in the seating step.
 
Spawn-Inc has the right idea. I believe it is called "LEE-menting" and a good explanation can be had on the Castboolits website. You use a layer of aluminum foil tape to increase the mould cavity a thou or two.
The wheel weights will likely have antimony in them which is just what you want. It increases the hardness of the lead. I believe quenching in water is required and also heat treatment in an oven. Again, castboolits website has all the info.
 
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I'm going to have to order some gas checks, I've called 4 local places today and all are sold out. I'm thinking it's the lack of a gas check is the source of my issues, as my alloy etc should be fine. I talked to a few guys that said they've had success without gas checks on the bullets I'm using but I think they may just be really good or really lucky. I neither good or lucky so I figure I'll have to try gas checks and go from there!

Thanks for all of the replys, and keep them coming!! Loading cast is something I want to do as I shoot all of the time so I want to save money and keep my mint barreled collectable guns mint for my lifetime!
 
Sounds like the too low pressure issue I was having with my 30-06 loads. Without enough pressure in the case upon ignition the case mouth can't seal itself against the chamber. bumping the charge up, and crimping should help with any blowback.
 
Spawn-Inc said:
with time they will get harder, not softer.
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Wondering where you heard this. Every source I have read talks about lead "age softening". It can be heat treated and different alloys and additives can increase or decrease the rate of age softening. After heat treating the hardness can increase for a number of days but will eventually start to age soften in the longer term.
 
.303 cast bullet loads

using smles and a p-14 i got good results only with gaschecks,2 inch groups or slightly larger using 2400. i'd save the red dot for shotgun and handgun loads
 
See if Henry at budget shooters supply still has gas checks.

As I related in other places, my (7.62x51) Mauser does the same thing and I was getting strings of solid lead coming out. Going to try the .309 sized stuff tomorrow and slug my bore whenever I get to it.

I have always cast with #2 alloy, otherwise, and have never bothered with water dropping or heat treating or any other faffery. To this point that has worked fine.

For the liquid Alox I tried using ziplock freezer bags and just worked it like a stress ball. Seemed to work quite well.
 
your bullet may be too small IDK about the ross for groove count but the lee enfields have different groove counts some can be measuered as normal but ones like 5 groove need to be rolled in the jaws of the calipers to get a measerment also the throat may be larger then the muzzle id have my bullets at throat diameter

i use red dot alot never had this problem my bullets are .315"-.316"
 
handofzeus said:
Sounds like the too low pressure issue I was having with my 30-06 loads. Without enough pressure in the case upon ignition the case mouth can't seal itself against the chamber. bumping the charge up, and crimping should help with any blowback.
Click to expand...

Yep that's what I thought to, forgot to mention that as I tried that yesterday with even worse results! I crimped and encased the charge but got more leading and more soot on the case mouths! I'm thinking gas checks will solve my problem.

Oh well I must keep shooting so until I get some gas checks I'll just have to load my regular hornady 174 grain round nose/ 4895 recipe. My Mauser is so badly fouled that I think I'll have to spend some time in the basement scrubbing this weekend.
 
Not sure if this helps, but I've gotten excellent 50 yard accuracy with .313 gas checked 180 grain bullets, and 13g of red dot. The grouping was around half an inch with no leading.
 
I have a few things to try:

a. slug the bore again. Undersized bullets are a major source of leading and your results seem suspicous;
b. use a gas check, or use a plain base bullet. Gas checked bullets are prone to leading when their base is left exposed; and
c. once a. and b. have been addressed, lube and size them with Alox again - they might be underlubed.

Don't try to make the bullets even harder. Hard bullets are more likely to lead than soft, at the pressures you'll be getting from "The Load" (13 grs of Red Dot). WW is fine - no need to water drop. You don't really need gas checks either at those pressures.
 
Spawn-Inc said:
I can't remember the name of it but if you put a thin layer of tape on your mold blocks it will produce bigger bullets. I've never tried it as it seems like it would make fins and through off the concentricity/roundness of the bullet.
Click to expand...

use real aluminum duct sealing tape.

gunstock said:
Spawn-Inc has the right idea. I believe it is called "LEE-menting" and a good explanation can be had on the Castboolits website. You use a layer of aluminum foil tape to increase the mould cavity a thou or two.
The wheel weights will likely have antimony in them which is just what you want. It increases the hardness of the lead. I believe quenching in water is required and also heat treatment in an oven. Again, castboolits website has all the info.
Click to expand...

the technique is called "Beagling" named after Larry Goins I believe, who goes by the handle Beagle.

You use slices of tape on one face of the mould, going around the cavities.

if still dropping too small, do the other side.

some have reported good success with 3 layers, but depends on the thickness whether you get flashing or not.

also, the "out of round" doesn't seem to be too big an issue. Some size, some load as cast and let the bore do the sizing.

Andy said:
I have a few things to try:

a. slug the bore again. Undersized bullets are a major source of leading and your results seem suspicous;
b. use a gas check, or use a plain base bullet. Gas checked bullets are prone to leading when their base is left exposed; and
c. once a. and b. have been addressed, lube and size them with Alox again - they might be underlubed.

Don't try to make the bullets even harder. Hard bullets are more likely to lead than soft, at the pressures you'll be getting from "The Load" (13 grs of Red Dot). WW is fine - no need to water drop. You don't really need gas checks either at those pressures.
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+1 on what Andy sez.

Also try this: Fire a factory round in it, and then take your chamfer tool, and put a good chamfer on the inside, then VERY Carefully measure if you can.

if unable to measure, just slide a cast bullet into the case. Best fit seems to be when the bullet JUST fits, with very slight resistance to finger pressure.

That will be the largest diameter bullet that, usually, can be fired out of the gun without much dinking around, and it will be safe.

if you can, find some pin guages and check your brass for fit that way if you are unable to size in 0.001 increments.

like Andy said, a slightly softer bullet seems to lead less, and one that just fits into the neck will provide the tightest fit in the bore.
 
LUTNIT said:
Wondering where you heard this. Every source I have read talks about lead "age softening". It can be heat treated and different alloys and additives can increase or decrease the rate of age softening. After heat treating the hardness can increase for a number of days but will eventually start to age soften in the longer term.
Click to expand...

it was on cast boolits, but now that i look for the info, it may have been oven treating them that they got harder with age. here is an article about it,
http://www.lasc.us/HeatTreat.htm


nanuk said:
the technique is called "Beagling" named after Larry Goins I believe, who goes by the handle Beagle.
Click to expand...

That's what it is!
 
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