Bolt Selection

The ACS seems to be hit and miss. Some of them still have chopping probs due to the spring not being light enough. If it does chop it's recommended to just stick a barrel swab in the feedneck and shoot it a bunch of times to wear the spring in. The ACS actually comes in delrin and alumunum configurations. Have heard mixed reviews on the Shocktech delrin bolts as well. What you gain in light material you lose by escaped gas on delrin bolts with no o-rings. With no o-rings there's nothing to keep some of the pressure from escaping around the bolt when pressure is released through the valve. Having o-rings keeps most of the gas going through the bolt where it should be going. My personal recommendation would be to just pull the venturi and polish the stock bolt. It will free up the flow of gas through the bolt which will allow you to use a lighter spring for the striker which will make it more efficient. Having a light spring on the striker will make the bolt less likely to chop as well. Having fresh batteries in your Revy will make it feed well and you shouldn't have to worry about chopping. I have an LP Spyder that rips and the Revy does a fine job of keeping up w/the rof -

Now if you must have a delrin bolt, I'd go the ACS and if you do have probs do what I typed earlier. Chances are it'll work just fine though but it'll just a little less efficient than the stock bolt -

That all depends on the differences in the tolerances between the bolt and upper tube. Most paintball marker manufacturers don't adhere to strict tolerances because markers aren't like actual firearms w/a need for strict tolerances. They will deviate from marker to marker. I didn't even mention the fact that with no o-rings this escaping gas around the bolt will possibly push balls back into the hopper as well(blowby) which can cause chopping probs. Until I drilled some holes in my 98c's feedneck I had a slightly similar prob with it since the bolt is made of delrin and has no o-rings -

My personal opinion is just stay away from delrin bolts especially with a marker that runs at a high pressure. I have a delrin bolt in my Imp and it affected the velocity a bit but it wasn't so noticable as a stacked tube blowback because it runs at 150psi. Considerably less than the 800psi that your dads Spyder is running at -

I have no scientific data that illustrates exactly how many shots of difference there will be, I'm just saying for the most part, a delrin bolt will only save a little scraping/scratching in the upper tube & bolt if you install a delrin bolt in a Spyder. Actually for the price of one of those ACS bolts you'd prolly be better off getting a faster feeding hopper like an Eggo. Chops are normally due to a slow feeding hopper not necessarily the marker itself -