J10 acr mod fps drop

Just wondering if anyone else has had problem with the acr.
I installed a new cylinder, oring (nice fit got good compression), alloy cylinder head and nozzle, fighting bro tight bore barrel, front barrel stabilizer and i have lost 20 fps from standard.
Few mates have had the same problem…
Anyone else had this?
Or know what is doing it?

Thanks in advance.

Assuming it wasn’t a ported cylinder, I was able to improve my blaster by 10-20ish fps simply by resealing the cylinder head to the cylinder…
I had put a sliver of Selleys Ultimate Repair (glue) around the cylinder head before squashing it back into the cylinder…

Otherwise, there’ll probably be a leak somewhere causing you the grief (nozzle to t-piece to barrel)

Unless you’re using anything but the standard milkies in the tightbore barrel? (never used a tightbore myself so I’m not an authority on the gels it takes well)

Come save us, gel veterans!!

Thanks man,
Nah not a ported cylinder, and yes only standard milkies in both my guns, both have tight bore barrel.
The barrel is all glued into the tee piece and sealed well…
The nozzle does seem to be sliding nicely and seems to be doing what it should,
On that note could be worth bit of glue on the cylinder head. Wont hurt.

It is about the 15 to 20 fps it has lost.

Thanks man i will give it a go.

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Did someone call a vet :stuck_out_tongue_closed_eyes:. You mentioned the new barrel is a tight bore. But how tight is she?:thinking: (punn intended). Are we talking 7mm or 7.2mm? And is the new barrell the same size as old one or longer as the fps will if you drop if you drop a longer barrel in without stronger spring?

Definitely seal that head up. Or another option is to get a one piece cyclinder and head. No leaks there

7.0, and ut is a little longer as the internal area would be different to the standard being so much smaller. But even then now has a 1.25 spring in it…

If you still got the last barrel swap that back over and see if that improves coz I got a feeling that’s the cause. The gels might be a little to snug in the 7mm. As I’ve had that issue too so opted out for the 7.1mm tight bore and funny enough 0.1mm made all the difference

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A gel that is, say, 7.4mm being forced down a 7.0mm barrel will have to become oblong to get down the barrel… then, with X amount of compressed air pushing it, the back of the gel will possibly become concave, pushing the gel out towards the barrel, causing much friction.

Engineers on here are welcome to correct me, but I think the gel should be about .2 of a mm smaller than the id of the barrel… so the ball has a little clearance, but when the compressed air pushes it, the gel expands to make a reasonable seal on the barrel.

If the gel is too small, like a 7mm gel in a 7.5mm barrel, the air will just go around the ball and it will not go far, or maybe fall out of the end of the barrel … DoH!!

It is not too difficult to change out barrels… it might be an idea to measure your gels and change barrels to suit…

BTW, gel blaster barrels and gels make awesome pea shooters :cowboy_hat_face: