Meteor dreams have come true

[evert]

Very nice Evert. 10 fpe for a Meteor, that is very "healthy".
Is that just a matter of a stronger spring?

Did a follow up chronograph session after a couple hundred shots the last days.
I also weighed the Gamo Match pellets to be sure the numbers are corrct.
The Gamo Match wadcutter gave me an average of 760fps the last time, and were claimed to be 7.7grs, giving an energy number of 9.9fpe.
They weighed 7.6grs on my MTM scale, so the real energy number is 9.75fpe for the last chronograph session.

After some shooting, I get the following numbers, all average of 5 shots:

-Gamo 7.6grs match: 743fps or 9.3fpe - the spring may have taken a set, or lubrication may have been burned off?
-JSB 7.33grs RS: 699fps or 8fpe
-JSB 7.9grs Express: 719fps of 9fpe
-JSB 8.44grs Exact: 678fps or 8.6fpe

With these numbers and other observations, I have made some other speculations:

-the rifle dieseled with the light 7.33grs RS, and gave a quite high extreme spread between shots at 17fps variation. The light pellet with a soft skirt also gave noticably less power than all other pellets, perhaps indicating slam?

-7,9grs Express have proven very accurate in this rifle, and had an extremely low variation between shots, at 4fps max.

-The cut down spanish Supersport barrel on this gun had no breech chamfer before I cut a very small 45degree taper.
Original Meteor barrels tend to have a deep, large breech taper. Could it be that the breech taper and the mechanism combined favors pellets with stiff skirts? I need to try some RWS pellets with stiff skirts to see how they perform!

[jirushi]

@ John, that Mercury looks super nice! Wow.

@ evert, it will be interesting to see results with RWS pellets.

My Meteor works best with 15.89 gr JSB's.
I did a few shots yesterday evening, 144 - 145 - 146 - 144 - 144 m/s. About 476 ft/s.
That's 8 ft/lbs. I think just right for a Meteor. The Mk1 trigger mechanism is such a big improvement.

I have had a Meteor that did about 10 ft/lbs, but I think that's a bit too much for this platform?

[evert]

I have had a Meteor that did about 10 ft/lbs, but I think that's a bit too much for this platform?

I dont think so, if you have a good one that gives power easy.
The one I'm working on right now feels very good and is quite easy to shoot, even if it is giving more than 9 fpe with some pellets.
And this is a .177, I might try the .22 lightning barrel I have on it and see what happens.

Tried some RWS pellets yesterday, after weighting some pellets to be sure what weights they are:

Superdome 8,5grs: 677fps or 8.65fpe, 10fps variation
Rws wadcutter, 7,3grs: 758fps or 9.3fpe, 18fps variaton
Meisterkugeln, 8,2grs: 672 or 8.2fpe
RWS Supermag 9.4grs: 597fps or 7,44fpe, and an EXTREME 30fps variation.

So, conclutions so far:
Light pellets with thick/stiff skirts (RWS wadcutter, and Gamo match) giver better energy than light pellets with soft/thin skirt (JSB RS)
Medium weight pellets give low variation (JSB express and RWS Superdome)
Heavy weight pellets are useless in medium power springers.

I'm sticking with JSB express, which has given good accuracy in other Meteors too.

[evert]

My Meteor works best with 15.89 gr JSB's.
I did a few shots yesterday evening, 144 - 145 - 146 - 144 - 144 m/s. About 476 ft/s.
That's 8 ft/lbs. I think just right for a Meteor. The Mk1 trigger mechanism is such a big improvement.

I have had a Meteor that did about 10 ft/lbs, but I think that's a bit too much for this platform?

Hav you tried 14,33grs JSB express? They give very good accuracy in my .22 lightning, and are theoretically
better suited for a powerplant with light piston and thin wire spring (like the meteor).

[jirushi]

Hav you tried 14,33grs JSB express? They give very good accuracy in my .22 lightning, and are theoretically
better suited for a powerplant with light piston and thin wire spring (like the meteor).

That's a good tip, thank you.
I tried 14.35 JSB this morning, power is now 9 ft/lbs.
The 15.89 gr fits better in the barrel, as in the skirt is a bit thicker, so the pellet stays firmly in the barrel when closing the breech.
I will test accuracy with both pellets soon.
Shooting behaviour is the same: nice.

The Titan silencer makes cocking easier.

[evert]

That's a good tip, thank you.
I tried 14.35 JSB this morning, power is now 9 ft/lbs.
The 15.89 gr fits better in the barrel, as in the skirt is a bit thicker, so the pellet stays firmly in the barrel when closing the breech.
I will test accuracy with both pellets soon.
Shooting behaviour is the same: nice.

The Titan silencer makes cocking easier.

I think breech tapers varies a bit on the more recent Lightning/Supersport barrels too. Not as much as on the old Meteor barrels though, but enough to affect pellet fit.
The silencer brings the length of your 10" inch lightning barrels up to about the same length as the 14" BSA Carbine barrels, which I personally find to be the shortest length that is easy to shoot well.
I'm considering to try steel baffles in one of my XL Lightning shrouds, because I find the shroud to be too light on the 10". The older Lightning silencer is better balanced for good shooting.