Shot inconsistency.

[liam88]

Having a mare with my m4 at the moment. Im running a prowin cnc and madbull blue. But the consistency is awfull. Resorted back the the g&g green with better effect but strughling to hit 40m I was previously hitting 50.

So basically I think its the hop rubber. What is a good alternative to the madbull blue?

I never liked it since it was to tight to fit in he unit and trimming was requieed.

Ta all

[johnnyj]

Re: Shot inconsistency.

have you made sure your nozzle fits the prowin ? not a lot of m4 nozzles will fit the hop unit

[liam88]

Re: Shot inconsistency.

Ive ran the prowin for months with no issues. Nothings changed. When I changed the rubber for standar g&g it improved but wasnt great. Thats why im thinking rubber or nub. Think I may just r hop and be done with it

[happyal]

Re: Shot inconsistency.

In my experience inconsistency is always caused by an air leak. I would check the piston O-Ring and the nozzle and make sure you have got the gearbox sorted before checking anything further forward. Once you know that the gearbox is good you can focus on the hopup rubber and hub.

[WTP_Trust_ME]

Re: Shot inconsistency.

^ this x1000

[liam88]

Re: Shot inconsistency.

Air seal is fine as is the gearbox. Striped and rebuild several times. Time for another look.

[WTP_Trust_ME]

Re: Shot inconsistency.

I have had a hop ubber make 100fps worth of difference before mate. That said, madbull blue's have always worked well for me.

Is this an M4? If so does the hop fit nicely in the outer barrel? I have had a few which are hella tighe whi causes problems.

[liam88]

Re: Shot inconsistency.

hop fits in the barrel fine, only thing is the original hop unit and also the prowin never had a spring for the front of the hop, its a g&g top tech btw, im looking to r hop now and have seen someone suggest and post a link for silocon tube, so going to try that.

[laurence]

Re: Shot inconsistency.

You could try isolate the problem. So replace the prowin with the original hop-up unit, then try both rubbers with that hop up unit, then try both with the prowin, you should be able to diagnose the exact problem from there. Ive heard many people have inconsistencies with the prowin hop-up units before so replacing it with the original one may be able to solve it.
You also said the madbull one was a tight fit, have you looked down the barrel after installing the barrel back into the hop-up unit to check its smooth and that adjusting the hop-up works fine? I had a problem with one of the madbull hop-ups grabbing on the rubber as i put the barrel back and it stretched the rubber so it would be pretty warped. If so, try a bit of silicone spray on the outside just to ease it in

If none of this is the case or works, then try the nozzle, and see if it makes a good seal with the rubber by firing it and putting your finger into the magwell just behind the unit and see if a lot of air is escaping there.
other than that, it must be a gearbox problem.
hope this helps

[liam88]

Re: Shot inconsistency.

Gearbox has been stripped and thourily cleaned and degreased. Will rebuild tomorrow. Also ordered an guarder soft clear rubber and h nub so shall see how that goes

[WTP_Trust_ME]

Re: Shot inconsistency.

hop fits in the barrel fine, only thing is the original hop unit and also the prowin never had a spring for the front of the hop, its a g&g top tech btw, im looking to r hop now and have seen someone suggest and post a link for silocon tube, so going to try that.

That spring is important - if the hop isnt being pushed (by the spring) against the gearbox it may not seal properly

[liam88]

Re: Shot inconsistency.

The original hop never came with said spring either. Had two top tecs and both have been the same.

Its a mystery. .... ha

[jonny lovegrove]

My toptech didnt / doesnt have a hopup spring. And the seal is good enough to do 385fps on an m100.

[Genesius]

Re: Shot inconsistency.

Go with the guarder clear and H nub, it's what I use and I've not found anything better yet.
It may be that the air nozzle is cracked or worn. For a few £ just replace it. Then, and this is something I do to all my guns, take a deemed and sand the from of the tappet plate but about .5mm. Not the bit that retains the nozzle, just the bit that hits on the front of the gearbox. That will cause the tappet plate to travel further forward creating a better air seal as the air nozzle goes in that extra bit.

Good luck

[liam88]

Re: Shot inconsistency.

The guarder seemed to fix things for a mag but now I think ive stripped a piston