Preload on original springs in a 1914 PSA Standard.

[45flint]

Curious if any of you have seen what the original preload on these PreWW1 Standards were originally. I had one with a broken double spring and if measured the two springs would go to the end of the end of the tube when loaded. It seems most would preload a inch past tube. I just wonder if this is a way of increasing the power when it was not they way they were originally made.

[silva]

There must have been preload on the original springs as in the little foldout booklet that came with them originally, it demonstrated placing the rifle muzzle down and compressing the spring into the cylinder using the stock and trigger block section. Edbear who unfortunately seems to have lost access to this forum would be your man for this info, as he did quite a lot of work on spring lengths, but I think you can find him still on the other airgun forum.
There is quite a bit of his info in the technical section of Dannys excellent vintage airgun resources too.

[45flint]

There must have been preload on the original springs as in the little foldout booklet that came with them originally, it demonstrated placing the rifle muzzle down and compressing the spring into the cylinder using the stock and trigger block section. Edbear who unfortunately seems to have lost access to this forum would be your man for this info, as he did quite a lot of work on spring lengths, but I think you can find him still on the other airgun forum.
There is quite a bit of his info in the technical section of Dannys excellent vintage airgun resources too.

That booklet is a pretty good indication for sure. Thanks. Could be that over 100 years of compressions shortened them a little?

[isobar]

That booklet is a pretty good indication for sure. Thanks. Could be that over 100 years of compressions shortened them a little?

double springs in my standard with about an inch preload.the rifle shoots fresh,powerfully and smoothly.

[45flint]

double springs in my standard with about an inch preload.the rifle shoots fresh,powerfully and smoothly.

Are they original double springs? Wonder if there was a difference between PreWW1 and after the war? I doubt my double springs could have compressed an inch? Eddie has a fascinating series of comments in the “Gallery” under BSA resources.

From the Gallery:



“The top one is a N.O.S. BSA Airsporter which measures 10 1/4" overall, with a wire gauge of 0.127" x 33 coils. The second set are a set of pattern twin springs, in 0.134" wire x 17 coils, these are 10 1/8" long, and were removed from a gun as it was very harsh and over the limit! The third set are a set of original BSA twin springs, these are 0.136" wire x 17 coils , a stiff temper, and are 9 1/4" inches overall..this gives minimal preload, and these springs give mid 11's in energy and are very smooth in operation. You will notice the striking difference in the length between the pattern and genuine twin sets, due to the more open winding...” Eddie

Mine must be orginal as they are identical to the last set in the picture and he says they produce mininimal preload. They are a tighter coil which is not available now. Replacing them with modern springs adds preload to match power? But I think it produces more snap in feel? My choice seemed to be to reduce the preload and power to give me a pleasant feel? But feel is in the hands of the shooter I guess.

My original springs with the broken one pieced together. Same as Eddie’s third set 17 coils with minimal preload?

[evert]

Mine must be orginal as they are identical to the last set in the picture and he says they produce mininimal preload. They are a tighter coil which is not available now. Replacing them with modern springs adds preload to match power? But I think it produces more snap in feel? My choice seemed to be to reduce the preload and power to give me a pleasant feel? But feel is in the hands of the shooter I guess.

Your first goal should be to not over stress the piston and sear surfaces by too much spring force.

I'd start with a single spring that fits mid power guns like the old HW50, and see if it needs cutting.

[isobar]

i will have a look inside,i have not dismantled the rifle for several years so my memory may have failed slightly.now to get the guard screws out without damage.

[isobar]

i've had a look to refresh my memory,i'd forgotten how easy it is to strip.there is about half an inch pre-load,17 coils to each spring and each is about 4 and 3/4 inches long.one spring is slightly shorter by about a 16th.i guess they are original to the rifle as they have the pylarm mark(clearly visible on one end) and with a loupe i can see a small s stamped?they look very similar to your springs minus the break.mine is a slightly later model c1919.i hope that is of some use to you.

[45flint]

i've had a look to refresh my memory,i'd forgotten how easy it is to strip.there is about half an inch pre-load,17 coils to each spring and each is about 4 and 3/4 inches long.one spring is slightly shorter by about a 16th.i guess they are original to the rifle as they have the pylarm mark(clearly visible on one end) and with a loupe i can see a small s stamped?they look very similar to your springs minus the break.mine is a slightly later model c1919.i hope that is of some use to you.

That is what was amazing to me, these rifles are so easy to take down. Looks like the same or similar springs to me. I think that the tighter wind and stiffer spring work better in these rifles and give them the best performance? Replacing them with modern springs probably is a compromise, but life goes on they still work fine. You have an advantage cause you have experienced what the originals were like. I have to just be satisfied with what feels right to me with an eye on not putting any more strain on an old rifle.

[isobar]

That is what was amazing to me, these rifles are so easy to take down. Looks like the same or similar springs to me. I think that the tighter wind and stiffer spring work better in these rifles and give them the best performance? Replacing them with modern springs probably is a compromise, but life goes on they still work fine. You have an advantage cause you have experienced what the originals were like. I have to just be satisfied with what feels right to me with an eye on not putting any more strain on an old rifle.

these springs certainly suit this rifle,it fires with a gentle thud and no twang,my wife thinks it sounds like a bow.it is however deceptively hard hitting.Eddie is really good on springs and all things bsa for that matter.