Air Arms Pro Sport tuning - going supersonic

[boomBBQ]

Hi everyone!

Is it possible to tune a Pro Sport myself and fit it with a less powerful kit? If so, which kits do you recommend? Is airgun tuning something I can learn and do well on my own or do I risk ruining an expensive springer?

I recently received my new Pro Sport and realized too late that I had bought the FAC version. I can't return it since it was a special order left-handed walnut, which is not generally stocked by retailers.

It's not enjoyable to cock the lever -- I feel like I'm going to get a hernia or dislocate something every time! Worse off, I'm pretty sure my lighter pellets (like the ~5gr "green" pellets) are going supersonic. I hear a very loud and distinct bullwhip-like crack whenever firing lighter rounds and worry about alarming my neighbors.

Thanks for the help!!

Gus

[Motorhead]

While Iv'e witnessed very few springers that can shoot any lead to supersonic speeds, the light alloys if you say so ... ok.
If that light of a pellet is what you choose to shoot, INDEED detune the rifles output.

[Hoppalong Doc]

     You DO NOT want to to shoot your Pro Sport with pellets going supersconic. Use heavier, lead pellets that shoot less than 850 fps for best accuracy.  There are plenty of YouTube videos on-line addressing tuning your rifle,  but I must ask why? Shoot your new Pro Sport a couple thousand times and get to know it's characteristics. I'm afraid that it will always be a hard cock . . . but it should be a tack driver, so go shoot it!. Orv

[boomBBQ]

I'm trying to keep to lead free pellets, for reasons. Those are lighter and go supersonic it seems.

Also, I'd like to detune this so I get better accuracy and of course easier cocking.

Assuming my only option is change my spring, do you have any recommendations for my original questions on the tuning route?

thanks so much

[Roadworthy]

I've never worked on a Pro Sport but my TX 200 is probably the easiest airgun I've ever seen to disassemble..  I like the products from Air Rifle Headquarters and they carry springs and seals for the Air Arms guns.  You can email requirements and they'll even respond with suggestions.  You may even still be able to order a twelve FPE kit for your gun.  The non lead pellets are really pretty light and it is possible for the less resistance of a lighter pellet to cause your spring to fail prematurely.

[Tater]

Moved to the UK Gate.

[DanD]

Hi, Gus,

There are some options....

You could try clipping a coil or two off your spring, but make sure you keep some preload so it's not loose in the chamber. AA guns come with fairly low preload so I'm not sure how much room you have to clip.

You could contact http://airrifleheadquarters.com and see if they have a drop-in low power spring or can make you a kit.

Vortek Products makes a drop-in 12 fpe kit that would lower the power.
http://vortekproducts.com/ourstore/PG3-TUNE_KITS/PG4_TX200-ProSPORT_air-gun

Tinbum in the UK makes short stroke extensions and kits with guides, but beware their kits come with full power springs so you can contact them about a softer spring or clipping coils, etc. https://www.airrifletuning.com

So, who ordered the lefty walnut PS for you and how does it look?
-
Dan

[Frank in Fairfield]

Lead occurs naturally.
It is all around us.
A silver mining company in Oregon found so much lead while harvesting the silver, they started making and selling silver bullets.
Lead bullets with a silver coating.
Just don’t eat it.
Shoot it and enjoy.

[EMrider]

If you need/want to shoot non-lead, then use the GTO 6.8gr domes.  They are the heaviest non-lead option in .177 and I have found them to be very accurate.  Downside is that they are expensive.

IMHO, the pro sport cocking lever design is not optimized for US market power levels.  The gun is easier to cock and wear on the cocking lever attachment bolt is much less at 12fpe or thereabouts. 

Not sure why, but ARH does not offer tune kits for the air arms spring guns, however, you may be able to buy a 12fpe spring. 

I have had good luck with the Vortek 12fpe kit in my pro sport.  It gives me about 11.7-11.8fpe with the JSB 8.4s.  Very nice shot cycle and great accuracy.

Good luck

R 

[Jay308]

My TX200 manual says, only use lead pellets. Maybe they are too light and cause the spring/piston extra wear?

[justinp61]

I'll hazard a guess that even the sub 12ftp versions are not designed to shoot super light alloy pellets.

[Jim-in-UK]

The Pro Sport is supplied with one of two springs. The 'Export' spring has a rate of 46 lbf/in, and the UK spring is just 30 lbf/in, which obviously makes it far easier to cock.

UK spring specifications are 20.8mm OD, 2.9mm wire, 23 active coils, free length 235mm (new) 223mm (settled).

Around 25mm of preload should get you around 11 ft. lb.

[KWK]

This type of underlever is always easier to cock by placing it on your left hip/leg and pulling with the left hand. Reverse for southpaws. It's just easier.

[boomBBQ]

Thanks for all the tips everyone! I'll try out some of these pellet recommendations and the mentioned tuning kits.

I see Vortek kits mentioned around here a lot so that seems a great place to start. It's also encouraging to hear that others have done this themselves without messing up their rifles. I'll also check out Air Rifle HQ as suggested.

I own several springers so I feel I have a fair and varied set of references about cocking force. The Pro Sport has lower leverage due to physics, but the FAC version I have also seems to have a much stronger spring as others have suggested with the different specs here.

I've tried many varieties of cocking holds -- sometimes even holding the rifle upside down. One of the best for me, when seated, is to place the butt on the inside of the left thigh/groin, and cock with my right hand. I'm actually right-handed and right-eye dominant, but suffered a sight injury and am blind on that side now, so had to retrain to shoot with my left eye.

[Stewie]

I'll second the Vortek kits and the comment about AA guns being a breeze to work on. My PS out of the box was pretty harsh, but after auditioning a couple of lower powered springs, settled on one that gives me about 11.5 ft lbs. That and a suppressor make it very quiet as well.