AA Prosport power

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marks dog bruno
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Joined: Mon Mar 05, 2018 12:51 pm

AA Prosport power

Mon Mar 05, 2018 1:41 pm

Hi all my first and was hoping for a little advice, I had my prosport from new so its never been tampered with and its had about 3 tins of pellets through it and as a local clay shooting ground is now catering for air guns I have been shooting more and the prosport is doing very well and decided to put through my COMBRO CB-625 Mk4, I put 10 shots down using AA Diadolo Express 7.87 grain and got 831-830-831-829-827-830-834-829-827 , the Crombro reads 11.9 foot pounds but as the CB-625 only lets you enter pellet weight in 3 digits and using 1.77 pellets I can only enter 07.8 instead of 7.87 so I took an average of 830fps and used an online calculator and it read 12.04 :o I'm quite worried now that it might be over the limit or am I reading it all wrong? I do clean it probably more than it needs but I never clean the inside barrel with any lube or oil so I'm fairly certain its not dieseling, any advice would great thanks .

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Re: AA Prosport power

Mon Mar 05, 2018 10:30 pm

830 * 830 * 7.87 / 450240 = 12.04 Yes it is over the limit on those figures.

Now why it is illegal and factory standard I have no idea - unless the combro is out. Try an other chrono?

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Re: AA Prosport power

Wed Mar 07, 2018 10:36 am

just take out a washer from behind the spring , that will reduce it down . adding more grease to the spring will help too in the mean time .

contact Timmytree on here for expert advert :-) .

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Re: AA Prosport power

Thu Mar 22, 2018 1:42 pm

As Julian says, simply remove a washer from the rear of the spring guide/spring.
Very simple to do and will only take 15 minutes.

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