Prosport cosistancy

[EV2UK]

Hi guys.

I have a factory new Prosport with a build date of December 2016.

Only had it a few weeks and haven't really had a play yet.
I have however tinkered woth the trigger slightly.

Ran it through my Chronograph today and it is very consistent..
The problem is that it is very consistantly around 812-818 with 8.4g. 177.



I did notice that it has 5 washers on the spring guide when I took the trigger block off.
Is it just a case of removing a couple of these.?
I'd like it to run around 11fpe and not the current 12.4 it currently is.


Chronograph assumed to be correct as my EV2 is still being read perfectly.



Tony

[tinbum]

I would take them all out and re-test. You will then know roughly what each should give you back when reintroduced.

[thisisdonald]

Love it! Straight in and to he'll with the warranty! A man after my own heart!

[EV2UK]

I waited almost a fortnight Donald.

[tinbum]

I waited almost a fortnight Donald.

Man, that's some iron willpower there! I usually rip the box open with screwdrivers to save time!

[cooper_dan]

Make sure you keep the washers somewhere safe!
My tx200 started at 13 ft-lb with 8.4 grain aa fields.

I took the washers out and it came down do 11.3 ft-lb. Perfect
After a few thousand shots it settled down to 10.5 ft-lb and stayed there. Unfortunately by this time i had lost the washers and had to get new ones.

I'm no expert but it sounds to me like the air arms springs aren't 'set' from the factory, therefore they need shooting a bit to bed them in.

I'm now planning on selling my tx200......to buy a walnut pro sport! Can't wait

[NickG]

leave it cocked for a couple of days to scrag the spring

[StellaArtois Sr]

leave it cocked for a couple of days to scrag the spring

Please correct me if wrong but don't you compress a spring to Scragg it rather than stretch it.

[tinbum]

Please correct me if wrong but don't you compress a spring to Scragg it rather than stretch it.

Yep, it'll be compressed.

Won't work though.

[Rich]

My guess is, you'll keep two of the washers in.

The spring will be working within its elastic limit, that means any deformation is restored once the load is removed. The exception to this is the phenomenon of creep, where very slowly the granular structure re-aligns if a load is applied long enough and large enough, and importantly if the temperature is high enough. Metals usually have to be at a temperature about a third of the way to their melting point for there to be any appreciable creep.

Some years ago a RFD told me this idea of keeping the rifle cocked overnight would be enough to take the top of the power off, and was a lot easier than a strip down. I believed him, and tried the technique on a HW97 I had that was a little too warm and I wanted to take it to a competition in a couple of days. It spent 36 hours cocked, I tried it last thing before I went to bed and it was safe. The next morning it failed the comp chrono three times and I couldn't take part. How it "healed" itself I don't know. But the technique doesn't produce a lasting change.

[Airsporter1st]

My guess is, you'll keep two of the washers in.

The spring will be working within its elastic limit, that means any deformation is restored once the load is removed. The exception to this is the phenomenon of creep, where very slowly the granular structure re-aligns if a load is applied long enough and large enough, and importantly if the temperature is high enough. Metals usually have to be at a temperature about a third of the way to their melting point for there to be any appreciable creep.

Some years ago a RFD told me this idea of keeping the rifle cocked overnight would be enough to take the top of the power off, and was a lot easier than a strip down. I believed him, and tried the technique on a HW97 I had that was a little too warm and I wanted to take it to a competition in a couple of days. It spent 36 hours cocked, I tried it last thing before I went to bed and it was safe. The next morning it failed the comp chrono three times and I couldn't take part. How it "healed" itself I don't know. But the technique doesn't produce a lasting change.

I left one springer cocked for a month. The power did not change one iota.

[EV2UK]

Had it apart this afternoon and turns out it only had 3 washers and not 5 like I seemed to remember.

Took all three out and now getting a nice consistant 760-770

Only downside it that it appears to of lost its 'snappiness'
What would be causing the difference in feel.? ... I know it'll be because I took the washers out but can it be made snappy again without being short stroked. don't really enjoy cocking it as it is.


Many thanks

Tony

[tinbum]

Had it apart this afternoon and turns out it only had 3 washers and not 5 like I seemed to remember.

Took all three out and now getting a nice consistant 760-770

Only downside it that it appears to of lost its 'snappiness'
What would be causing the difference in feel.? ... I know it'll be because I took the washers out but can it be made snappy again without being short stroked. don't really enjoy cocking it as it is.


Many thanks

Tony

Dump the heavy weight/top hat and introduce some preload.

[lensman57]

I left one springer cocked for a month. The power did not change one iota.

As pointed out by RICH modern springs do not suffer creep or " memory " effect within their elastic limit. Had the theory of leaving a gun cocked to reduce power been true a car after a few months of use would have had to have all its coil springs changed as they would have been compressed for good.

A.G