is it the seals

So the gamo does some wonderful groups then impact Point goes astray. I've got new seals on the way but have just chronographed it. Seems a bit of variation to me.
What is the view of you more experienced technical ppl on this?
All pellets were weighed and sized.
high 694 low 650 Ave 668
shots all in 600fps last two didgets of numbers in order.
79,90,94,84,94,70,66,71,68,87,73,54,64,
58,50,68,59,68,55,60,64,65,56,57,62
Any thoughts appreciated.

Cheers. The rifle has been very problematic. I voided the warranty ages ago when I removed the mag due to pellet deformation . So that is out. I check the pellets are seated in far enough every shot. When I removed the piston it wasn't that great looking, so I think the crossman oil every 250 shots is something I'll start doing after the seal replacement. Due to fact it will group for x amount of shots, I don't think it's the scope,as it will start regrouping again without adjusting the scope (deviation is way to much from aim point to be just my shooting and wind. I've looked at that. Blame shooter first and work back from that) and Ive lock tighted the screws they haven't moved. The info the red dot is awesome, Ive been toying with the idea, as I'm going to turn it into the scrub gun/short range (if I can stabalise it) and keep the tx as a longer range rabbit Gun. Im stoked to know that the red dot is used by another shooter and will now look further into that option. Eventual I'll replace it and muck around with my shock gel and carriage idea.
So cheers appreciate the response.
Any one else with ideas or options I'd still love to hear them.

I'm pretty sure it's not deforming as I check it's sitting below the edge of the barrel, but I have a little pusher thing that I can seat it in further with so I'll try that tomorrow too double check. The seal is on the receiver side (model is roadster)
guns going to get stripped,internals cleaned, polished,resealed,relubed put back together making sure it's all tight and working well. Sighted in at 10 then 26 meters on open sights, if still playing up after that cut losses won't waste any more time on it.
Lots of ppl who's gamo work great for them, I may have just got a bad gun/model but hopefully just wants some tlc.

Edited by kruzaroad - 12 Aug 2022 at 11:55pm

So pulled the gamo open and had a good look. Not impressed. Done a bit of sanding to inside of stock as had rub points but at irregular intervals. It has ribs under it to hold bottom of receiver. All along one side and just front and rear on other side. Can't see that helping an even shock vibration pattern. But I may be wrong.

Had a worn rubber on one side, where pin that holds trigger housing/piston housing to receiver.

Piston seal was embedded with a chunk of lead right at seal edge.(bottom of pic)

Seal Edge crap too

Sprayed with brake clean to see what came out, metal filings and brown crap I assume is protectent for metal when shipping.

Have just got ahold of vaughans for new rubbers.Piston and barrel seal arivved yesterday. But will rember that for next time thanks.
I'm currently looking at piston which has so much space between it and the gas plunger it's been rubbing on the gas housing during cocking.

Need to make spacer. (sujestions appreciated)

The gas ram end has play where it sits in the rear housing.
Noticed that one of spring clips on trigger (previous pic) is broken.
I have nothing against gamo but I'm starting to think I scored a rifle made from parts taken off other rifles that didn't make the grade.
Sigh.

Edited by kruzaroad - 16 Aug 2022 at 4:13pm