loads and shooting my wilkinson 1892 webley

[ehsa]

i thought this post might go better here at least i hope so.i have been posting in the black powder cartridge section about this revolver and have received a lot of help. in this 1892 webley wilkinson i loaded 6 rounds in winchester new 45 colt cases 3.8 grains of trail boss cci 300 large pistol primers and they did very well although i dont know what the velocity or pressure was. i may reduce the load to 3.0- 3.5 trailboss next time for a greater margin of safety tho it may not need that as there is no sign of high pressure anywhere.i also have a box just accquired of fiocchi mk2 ammo which many feel is not good for this gun.my question is wouldnt the colt 45 cases which being longer have a reduced pressure say over the shorter mk2 cases if i used equal powder in both.it seems that a longer case would give less pressure with equal loads speaking of only smokeless powder.john

[Wayne Smith]

True enough, John - but the question is and will always be - what pressures is that revolver capable of handling? You have an old gun and, even though it is nitro proofed, is made of old steel.

What you are addressing is the expansion ratio of the cartridge - internal ballistics. Yes, the larger area the gas has to expand into reduces the pressure on the inside of the case. This does not change the pressure curve, and Trailboss has a very steep pressure curve. I.e. It produces pressure quickly and that pressure travels along the inside of the cartridge case until it hits the bottom of the boolit. Yes, it attenuates but I'm not sure how quickly that happens.

Someone will be along who knows this information much better than I and can explain it better than I.

[ehsa]

True enough, John - but the question is and will always be - what pressures is that revolver capable of handling? You have an old gun and, even though it is nitro proofed, is made of old steel.

What you are addressing is the expansion ratio of the cartridge - internal ballistics. Yes, the larger area the gas has to expand into reduces the pressure on the inside of the case. This does not change the pressure curve, and Trailboss has a very steep pressure curve. I.e. It produces pressure quickly and that pressure travels along the inside of the cartridge case until it hits the bottom of the boolit. Yes, it attenuates but I'm not sure how quickly that happens.

Someone will be along who knows this information much better than I and can explain it better than I.thank you wayne that gives me a better understanding of what is going on. what brought me to the question was i know from reading about the old british double rifles that by lengthening the case and perhaps making it thicker like on the rigby .450 and later the .450#2 the pressure was reduced. but i know very little about internal ballistics. it seemed that 3.8 grains of trail boss in a 445 mk2 being shorter than the longer 45 colt case could have more pressure. as i just got a box of fiocchi 455 i could shoot or pull the bullets and reload them but would that be better? my gun will apparently take any of them including scofield 45.thanks john

[Oyeboten]

I would expect the .455 Webley Cartrdiges of old were running about 12,000 PSI.

How much pressure is generated, and how fast it is acheived, it's duration...are of course a funciton of the particular propellant's burning characteristics, and how much room or air space it has in the Cartridge ( when applicable ), and also how heavy the Bullet is, which will have an effect on duration, of course.

[Wayne Smith]

I believe the Mk2 is what the revolver was designed to shoot, so it should be safe as yours is in good condition. This gives you the understanding of what it is supposed to shoot. Anything under that in pressure - no matter how it is achieved - will be equally safe as long as the boolit leaves the end of the barrel. Personally, if it were mine, I would be looking for a Unique or similar load in the longest case I could use to minimize boolit jump.

You don't have pressure equipment so you will have to rely on the manuals that provide that information for the cartridge case, boolit, and powder you use. That will give you a ball park understanding of what is going on inside the case.

[ehsa]

I believe the Mk2 is what the revolver was designed to shoot, so it should be safe as yours is in good condition. This gives you the understanding of what it is supposed to shoot. Anything under that in pressure - no matter how it is achieved - will be equally safe as long as the boolit leaves the end of the barrel. Personally, if it were mine, I would be looking for a Unique or similar load in the longest case I could use to minimize boolit jump.

You don't have pressure equipment so you will have to rely on the manuals that provide that information for the cartridge case, boolit, and powder you use. That will give you a ball park understanding of what is going on inside the case. you may be right about mkII fiocchi being safe and i think it would be alright. i could pull them and reload them as well. i have 2 cans of trailboss and only a partial can of unique. and i used to shoot quite a bit of unique in various revolvers and like it very much. especially in 45 colt. i will be traveling over the next week or so and will get back to the wilkinson after that.