Prewar air rifle powers?

[magicesperanto]

I quite fancy the old BSA underlever rifles, can anyone give me an idea of the power they have in decent order?

I would only be interested in .177, further to the above, how much power can the be made to produce?

[Garvin]

I quite fancy the old BSA underlever rifles, can anyone give me an idea of the power they have in decent order?

I would only be interested in .177, further to the above, how much power can the be made to produce?

https://forum.vintageairgunsgallery....qs-2/#post-504

https://forum.vintageairgunsgallery....qs-2/#post-514

[magicesperanto]

Thanks Garvin, so I guess finding one capable of 11.5 fpe is going to be tricky then.

[scooter48]

In the early 70s I worked on the railways at a place called Riiple Lane.A driver there tuned an old Lincoln Jeffries 22 for me and when I got it back it was phenominal.That mans name Terry Robb .top marks.

[vbull]

I re-built one a while back, did nothing spectacular, new spring from Troubled Shooter polished the cylinder, spring guide and a few other bits new seal trimmed and soaked in Neatsfoot oil etc and was shocked when I put it through the chrono. After a poor start it climbed to just under 10 ft lbs. then started to go down a bit and seemed to settle at about 8.5 ft lbs. Not bad I thought....

[ptdunk]

I asked about this a while back.
I have a 1910 light pattern that shoots very nicely at 5.5ftlbs with a new spring and leather washer.
The larger ones put out higher power, for example a guy at our club has a nicely shooting Club Special doing around 10.5 I believe.

Extremely accurate rifles when set up well and shot correctly.

Matt.

[D10bore]

Well me grandad told me ,he had a old bsa that he shot at a target pined to a fence,it went right through the fence and killed a cock pheasant sitting on the other side ,then ricochet up and knocked a woodie out tree ,they were powerful them olde gunsmike

[Phil Russell]

Sure were powerful ... about 3/4 the way through a telephone directory on a good day, then reused the pellet for the next shot.
Seriously though ... I think there are many exaggerated claims of what the old rifles did or can do. I have read that they can make up to 12 ft lbs but I dread to think what has been done to the insides to get that. Maybe an old Cortina suspension spring? Or maybe it is a case of dieseling enhancing the power.
I tend to think that about 10 is a nice top output, although 9 is perfectly acceptable.
Cheers, Phil

[Garvin]

Or maybe it is a case of dieseling enhancing the power.

I think this goes a long way to explaining the tall tales, Phil.

[slug-gun]

Some years ago I was in a gunshop when a man came in with a very clean 1920's BSA standard, 45 1/2" model, in .22 calibre and asked if the proprietor would chrono his rifle. He did so and using the original 14.5 grain Eley Wasp pellets, that rifle put out a ten shot string which varied from 695 to 703 fps, to give an average of 15 ft lbs. And no the rifle wasnt dieseling and I've no reason to think that there was anything wrong with the chrono. The springs were changed soon after!

The gun was smooth to cock and appeared to have the original twin pair of mainsprings inside it. It was smooth to shoot as well, everything in perfect harmony.

This performance is backed up by a letter in Guns Review from the early 1980's where the writer shot a similar .22 BSA at the flat face of a quarry 110 yards away. He reported that every pellet hit head on and were expanded flat by the impact.

Modern spring guns can exceed 15 ft lbs quite easily so there is no reason that an older gun with similar internal dimensions shouldn't do the same, although I am prepared to believe this one was exceptional, in the same way that occasionally an example of a modern rifle will for no apparent reason perform 20% better than standard.

[keith66]

Interesting to read the above post. I have a 1910 Bsa imp model d in .22, about 25 years ago a bunch of us were out plinking on a muddy creek. I had recently put a new spring in the rifle & was sitting next to a mate with a brand new RWS 54, we were shooting at tins out on the water drifting away from us. He said "I think that old thing is a bit over, bring it round & we can put it over the chrono (he had just bought one)
So i go round there & we put a ten shot string through it. It was running at a steady 16 ft lbs . So out came the spring & chop a bit off, put it back, 14ftlbs, Chop a bit more & got it to just under 12.
The original springs were knackered so the one i had fitted was one i had laying around It was from a fwb sport, it was the right dia but way too long so i had cut it down by at least 2 1/2" before we chronoed it.
By the time we got it to a legal level the spring had lost another 1.5 "
The washer was in good condition though i doubt original, What was impressive was the consistency, shot to shot variation was just 5fps over a ten shot string.
Thing with these old rifles is they are well made & there is a lot of swept volume in there, the pistons vary with some being much heavier. So there is a lot of tuning potential.
I remember talking to Terry robb about this & he reckoned he had tuned one that reached nearly 18ft lds. I would not be surprised.

[Garvin]

in the same way that occasionally an example of a modern rifle will for no apparent reason perform 20% better than standard.

I suppose it makes sense, Chris, that while some rifles just refuse to get up to 'average' power for that model - I once spent weeks trying to get a Feinwerkbau Sport above about 8 ft/lbs - others are always going to be unaccountably powerful.

But before anyone gets their hopes up that prewar BSAs somehow routinely achieve these exceptional power levels, be aware that the overwhelming majority of 45in rifles stay stubbornly at around 9 or 10 ft/lbs. give or take, which is surely more than enough for such venerable old ladies/gentlemen.

[scooter48]

I suppose it makes sense, Chris, that while some rifles just refuse to get up to 'average' power for that model - I once spent weeks trying to get a Feinwerkbau Sport above about 8 ft/lbs - others are always going to be unaccountably powerful.

But before anyone gets their hopes up that prewar BSAs somehow routinely achieve these exceptional power levels, be aware that the overwhelming majority of 45in rifles stay stubbornly at around 9 or 10 ft/lbs. give or take, which is surely more than enough for such venerable old ladies/gentlemen.

I don't know what the old Lincoln Jeffries that Terry Robb tuned in the early 70s but it was the most owerful rifle ive ever owned. I sold it to a gun dealer in Southend and he snatched my hand of it. It also had a no 12 aperture sight. Ive had many rifles since but none came near this gun for power.Idont know what he done to it.I currently have about 30 rifles,mostly BSAs and vintage.Love this forum.

[keith66]

Terry did once tell me that he had tuned one heavily, this included going to the extent of machining a new cylinder that was longer than the standard one, how much longer i cant remember, next time i visit his skip (i mean shop) i will ask him. If you look at a BSA standard or Imp mod d stripped down on the bench & compare the parts to an Airsporter or Mk 3 webley there are noticeable differences. Cylinders on prewar BSAs are noticeably longer (they share the same trigger block thread as that on the airsporter) Not sure if the cylinder to breech block barrel join is threaded or soldered?
Pistons vary a lot, some are thicker tube & one i have laying about has a rearward extension adding weight.
Be interesting to see what they are capable of if you had an fac of course!