2x 98’s shoot hard soft hard soft

What is the air setup on these guns?  Are you using remotes/Co2/HPA/X-chamber/regulators?

My first guess would be a problem with air flow screwing up the recharge rate.  Where the gun will be at full pressure, you take a shot, then take another shot before the pressure has fully recharged.  A couple things can cause this, mostly blocages in air paths.

Also, you might want to just clean out the valves.  I wouldn't reccomend an upgrade kit.  It would be better just to fix the actual problem.

Exactly which bolts are popping out?

Give us more detail and we can help you out.

yah the ones that snick said....
i have completely dissasembled both
and cleaned...
they are both co2, with stock drop forwards.
it has happened with my 20, 9, and 7oz tanks
i have not found a situation where it *always* happens
also does it with stock, and 14in barrels

If they don't stay in place, then you stripped the threads in the valve and Shadowminion is right.

I do not reccomend using loctite on those because I always off my powertube assemly when I clean my gub after a game.  I do, however, reccomend you you just hand tighten the bolts and not torque them down to the point it will be hard to get off.  I have heard of this happening since I bought my first Model 98 over 6 years ago, yet I have never done it myself on countless different guns and too many time on my on guns to count.  It is not hard to NOT STRIP THE VALVE THREADS.  Just put them back in and they are fine.

But, since you already probably stripped them, you need a new one of these: http://www.tippmannparts.com/index.cfm?fuseaction=catalog.pr odInfo&productID=379&categoryID=12

But taking your probable lack of experience with valve assembly/dissassembly, I would reccomend you buy this instead (at a very good price): http://www.countysports.com/shop/product.php?productid=2373& amp;cat=267&page=5

w1f1 wrote: why would stripped bolts do that? just because they allow the valve assembly to slide forward and back every other shot?

Exactly! You get inconsistent opening of the valve when it can move from the hammer blow...sometimes sticking in place thus delivering the full gas charge, other times moving to soften the blow and reducing the gas release.

I would definitely us LocTite on the screws, but select the Blue (medium) strength. That will prevent loosening but allow easy removal when taking the marker apart.

I've used heli-coils as a field repair to get someone through the day- it's not ideal, but will work perfectly fine.  

JohnnyCanuck wrote: I've used heli-coils as a field repair to get someone through the day- it's not ideal, but will work perfectly fine.

Heli-Coils done right should actually be a permanent fix. The next solution is to tap to the next size screw...and since these are blind holes, it will require bottoming taps to accomplish that.