Eureka! - Cast Bullets in the Lee Metford Cavalry Carbine

[Brian the Brit]

(This topic is probably more suited to the reloading forum but if Adam will indulge me perhaps it can remain here as an update on an earlier post?)

Some of you may recall that when I bought the LMCC it was always my intention to shoot it with black powder and cast bullets in order to preserve the original barrel and thereby prolong its useful life for future owners.

Sadly my early experiments were very disappointing as no matter what I did the bullets tumbled badly and were very inaccurate. My Australian 220 grain .314 bullet mould was designed for use with smokeless powder and the bullets just don't carry enough lube to keep BP fouling soft.

I then moved on to Red Dot and A2400 powders also without any real success. The bullets still tumbled alarmingly and went everywhere but into the target.

When I tried FMJ bullets over 37 grains of VihtaVuori N140 however, I was amazed by the accuracy of the now well-stabilised bullets and as a result abandoned cast bullet experiments for a couple of years.

Yesterday (don't ask me why) I decided to try hardened cast bullets to see if (as I suspected) soft bullets were stripping rather than gripping the shallow Metford rifling as they passed down the barrel.

I first sized a few home-cast wheelweight bullets (without lubing them) and then put them into the oven at 230 deg C for 30 mins before dropping them into cold water to harden. (This apparently gives a hardness equivalent to linotype)

Next I put the bullets through the sizer die again at the same time fitting gas checks and lubing the grooves with a proprietary beeswax/alox mix. Ideally this second sizing should have been through a die .001" larger then the first one to avoid work-softening the alloy.

I loaded 15 rounds with 20.5 grains of A2400 and took them to our 50 metre range this morning to see what happened.

To my surprise and delight all 15 rounds punched clean holes in the black of the target without the slightest trace of keyholing. It looks like the tumbling and poor accuracy problems have been solved.

My questions now are:

1. Does anyone know of a 200 - 220 grain .314 or .315 bullet mould designed for use with BP?

2. If not, and bearing in mind that the absolute maximum BP I can cram into a .303 case is 52 grains, do you think that the glazed board discs and beeswax cookie method as used in the Martini-Henry might overcome the fouling problem?

3. As the capacity of the case would of course be further reduced by the presence of the wads and cookie might a lighter, shorter bullet be an option?

I'd appreciate any thoughts on these issues, guys.

Brian

[Aughnanure]

Brian,

Have a look on the Swiss sites. People have had excellent short range results using .32 pistol bullets in the K31 etc and the twist is about the same.

I tend to think that ,in light of this,that it would be possible to stabilise shorter projectiles in the Metford.

Just a matter of striking the right ballance. I have been using cast 150gr in .303 with good hunting results, but as these are for scrub shooting and the range is seldom over 75yds, I've never been worried about target accuraccy.

Eoin.

[dromia]

Congratulations Brian,

Personally my limited experience with BP in the .303 case indicates that paper patching is the way to go as regards fouling. The problem with most .30 calibre cast bullets is that the lube grooves aren't deep enough to hold enough lube to keep the fouling soft so paper patch is the way to go.

Swaged bullets are good paper patched and you can get paper patch bullet moulds as well, however I've had good results with my standard Lyman .314 mould sized down suitably fo a paper patch, I lube them before paper patching, I don't know if it makes a difference but it does give me a more solid bullet shape for the patch. Paper patch also means your not taking up powder space with cookies and wads.

If you must go the lube route I'd make the stuff up a soft as you can without it running out of the grooves, my mix is beeswax and tallow with enough lanolin to mahe it runny enough.

Using a blow tube between shot also keeps the fouling soft.

Go for the thinest brass case you can, Prvi Partizan is thin walled, to get the most powder you can in also some compression is usefull.

I've often thought about trying the original method by fireforming the .303 cases parallel in a .410, filling with powder, compressing with siutable compression plug and then sizing in the neck for the bullet and to fit the chamber, maybe this winter.

[belgmart]

1st of all, Metford rifling is indeed relatively shallow, and was actually developed for BP and hardened lead bullets, to be able to shoot them with minimal bullet upset.

If I were to shoot a .303BP, I would make sure to have a bullet 0.001 bigger than the groove diameter (or identical), use a good BP lube (combination of Beeswax and olive or peanut oil) and maybe also add a grease cookie sandwiched between 2 wads of baking paper under the bullet. I would Use either Swiss no.4 or Swiss no.2, well compressed (if you want to get enough powder in...) - use a compression die and compress al least once, add powder, compress again., then seat the bullet on top of the powder (you just leave barely enough space to seat the bullet). Of course, a bore rider design would be ideal, as it gets most of the bullet already into the bore.

Blowtube after every shot to keep the fouling moist and you should be good to go. I agree about using a hard alloy, but I would add some tin to the WW's in order to improve alloy elasticity - WW's are rather brittle, so...