Webley & Scott Premier Model D - energy?

[RJVB]

I'm trying to find an estimate of the energy (or exit velocity) of a Webley Premier (Model D) air pistol (with the 4.5mm barrel). The only thing I've found to date is that it's very powerful for its size. Fitting for a country where the 'premium' car makers only disclose that their models make 'enough' power, but still
Any ideas?

[ashf9999]

The only way to know for sure is to measure it...but expect about 3 to 3.5 ft/lbs at most muzzle energy with a decent spring and seals.

[grego]

Quoting figures in Webley Air Pistols (Gordon Bruce) p.121

350 fps in .177 , assuming a pellet wt of 7.9, = 2.15 ft lbs

Sounds a little pessimistic

Just so happens I have an "E" in .177 in virtually un-used condition so as soon as I can get one of my Chronos to work, I will post result on here

Grego

[RJVB]

The Model D & E have the same ("stronger") main spring as far as I understand, so yeah, please do post!
I don't have any comparison (except to an Airsoft springer...) but the pistol does feel as if it packs a punch ... but it will only dent, not pierce the cover of a can that held a nice portion of canard confit from around 4m away. (Those cans are larger and somewhat heavier than the typical preserved food cans.)

(1 ft lbf == 1.3558179483314 J )

[grego]

Here Goes;

Tested with a virtually unused (maybe 40 shots from new) .177 Tempest useing 7.9 gn accupels, av 10 shots

Tempest av 395 fps = 2.7 ft lbs

Premier "E" av 465 fps = 3.8 ft lbs

BUT premier was accompanied by a lot of smoke and had a 30 fps spread (dieseling?).

Saying that, shooting it with the tempest it really does feel that much more powerfull with regards to cocking and recoil .

Easily my favorite pistol.

[RJVB]

Great, thanks! (You *are* saying the Premier is your favourite, right?)

Just for the record, those correspond to 1.99J for the Tempest and 2.80J for the Premier E (making it a bit more powerful than the Tanfoglio I've been drooling on ^^). Nice - I guess the figure should be comparable for my Premier D.

I presume dieseling is a sort of auto-combustion of oil? I guess you'd smell that, no? I opened mine, probably for the 1st time since it was built, and cleaning it with some WD40 on a rag I got out quite a bit of a black, sooty substance, esp. from the piston chamber. The piston seal was in perfect condition though, but so dry that it was quite a fight to get the piston out. Didn't really notice any smoke before the cleaning act, though. I'd be curious to know what you find when disassembling your E (should you ever do that).

BTW: how do you convert bullet speed and mass (and size?) to energy?

[richtel]

BTW: how do you convert bullet speed and mass (and size?) to energy?

Energy (ftlbs) =

V^2 (fps) * Weight (gns)
____________________
450240

[grego]

RJVB, I may be wrong but i think you will find 2.7 ft lbs = 3.66 joules

and 3.8 ft lbs = 5.16 joules (so a lot more powerfull than the Tanfoglio)

As far as I know, dieseling is caused by excess oil , the oil vapour combusts under compression and so increases power

Grego