I have a British .500 x 3" BPE hammer double rifle that is in great condition except for bad bores. A friend and I are in the process of putting cold forged liners in. At this point, the liners are in place but not glued in and with no extractor cuts. Chambers have been reamed. The rifling has a rate of 1 turn in 20".

I'm doing the initial load development with IMR 4198 and started with 48 grains/330 gn hard cast bullets with poly wadding as filler. I'm getting horizontal right and left bullet placement with crossing at 50 yds. Usual standing rest. Since the bullets were crossing I started decreasing velocity Until I've gotten down to 35 grains. The crossing is better but still there.

My thought is that I may need to go to a heavier bullet. My goal is to end up with a smokeless load and a blackpowder load that will regulate with the same bullet weight. The case will hold about 120 grains of FFG as I recall. I have some 350 and 400 grain bullets on the way.

The reason we haven't Loctited the liners and made the extractor cuts is to enable us to turn the liners and/or take them out and remove metal at the front end. This way we can shim to regulate if need be. At present they are extremely tight at the muzzles so they don't show. Extraction is vis cleaning rod.

Any suggestions? Am I on the right track with my thinking as to needing heavier bullets?

Your rifle may have been initially regulated for 440 grainers. It might be marked on the frame or barrel flats. Or might not be. Heavier bullets should go far in solving this problem.

The 20" twist is extremely quick for a 500 BPE. That might be a minor problem. But you need to lock the tubes down before doing any load workups. You have too many variables going to start working up and loads. Narrow down the possible problems.

Keep the muzzles tight, make adjustments back by the sling loop.
Turn the liner OD back there, and shim to regulate.
You can use .002" shim tape and use either epoxy or thick cyanoacrylate (high tech crazy glue) to place it on the liners.

Lather, Rinse, Repeat...



Cheers
Tinker

Tinker
That's a great idea. I'll try the heavier bullets first, but if I need to move the bullets more that makes a lot of sense.

What kind of profile would be needed to make this work? If I understand correctly we would start just back of the muzzle and taper the liner to about where the swivel is then then a straight section and then gradually back out to current diameter? Roughly how much total reduction would you start with?

If this works (assuming I have to do it) it would be great because it would maintain the pretty much invisible seam at the muzzles. The breech seams are hidden because we made the OD of the liner the outside of the extractor cuts.

Thanks
MACD

Inch or so of column at muzzles, taper to where you shim, then an equal amount of taper.
Shim both sides of your liner to get back to full-profile width, and when it's all said/done and the liners are in place you can TIG the seam at the muzzle.
It'll take care and prep, extra time to do it right - but it's the only way to go.

How much to turn off in the lathe?
As much as you can without going too thin on the liner.
Make sure that whatever you use to bond it will handle the clearance.
Also make sure your (thinned) liner will handle the hoop stress at it's thinnest point.
Blowing this thing up in your hands will surely suck big time!!



Cheers
Tinker

What an awesome project! How about some photos at some point?

I believe 440gr was the standard in those days for the 500 BPE. Graeme Wright's book will have a number of loads for it.

Often the 3" version was regulated for the light 340-360 express bullets( hollowpoints).
The 3.25" version was regulated for the 440 grain express( hollowpoint) or 480 grain solid.

My load for my 500 Hollis is 56 gr IMR 4198, about 11 gr of dacron and a 370 gr bullet. The original 3" loads were generally 340 and 380 gr bullets over 136 grs of black. These were later increased to a 440 gr bullet in both black and nfb loads. A few were even heavier with one Eley load using a 480 gr bullet and 63 gr of cordite. These last loads were pushing into the 3.25 inch loads that Jens refers to. Bottom line if you're just starting to get groups using such light charges and a light bullet you may need to bring the 4198 powder charge up to 40% of the black load and then start bumping up the bullet weights. If you need I can send you some of the 370 gr HPs I use and some round noses that are about 400 gr.
God luck with the lining project.
Best

Thanks for the information from everyone and the offer of bullets. I plan to try the heavier bullets as soon as I get a chance to drive to a friends house to pick them up. He has some 340gn and 405gn bullets. I'll try them with an increased powder charge.

This should get me going in the right direction. I may end up with something in between such as the 370gn bullet that 50 calshtr uses.

By the way 50 cal, have you shot your Hollis with black using the 370gn? Maybe wishful thinking, but I'd like to find a single bullet wt that will regulate with both black and smokeless.

MACD
Now that you ask, I have never tried black in the Hollis. When I got it about 30 years ago I was told by the seller it was regulated for the NFB loads. It's a boxlock hammerless so that seemed logical. Back in those days the go to powder was 3031 as it has about the same burn rate as cordite, getting the right load was a bear. 4198 is much better, thank you Ross Seyfried!!! Yell if you need some of those bullets, they're from a Lyman 440 gr mould I hollow pointed so if they work for you you might be in a bind getting it duplicated but it might be worth the try.
Best.

My Grant and Churchill 500's like 350gr hard cast bullets with 53gr of H4198.
I shot an elk with the Grant at 120yds and he dropped like someone pulled the rug out from under him. Bullet went through both shoulders and exited.
ND