ar 15 300 whisper conversion to ares GSR35 piston kit

[THE DOCTOR]

OK I had my Whisper running really well shooting MOA or better groups using 14.5 gr win 748 and 200g lead or 9.8 gr 4227 behind 220 gr Hornady RN so to throw a monkey wrench in the whole deal I thought why not convert it to a piston to keep some crud out of my chamber trigger, mag, magwell etc. Of course nothing is easy and it has not gone smoothly.......


I have lightened the piston return spring and it is still not ejecting fully which means i have a long way to go before it is even close to cycling. I would prefer not to ream a larger hole in the barrel but it may come to that. I am a machinist so it wouldn't be that big a deal but if i want to get back to the direct gas system it will make things more of a pain. The gas port is in the standard carbine position and is still stock diameter. Anyone using one of these on the 300 whisper and having success have any suggestions?

I already had this gizmo working on another 223 M4 so it is not the kit i am afraid it just needs more gas than my current setup is giving it.

Thanks

DOC

[jarhead1086]

I thought about this possibility before, but I have found that if I wait long enough somebody with more time and money than me figures it out. I think the pistol length would be better to start with, but then you have to modify the length of the GSR-35 piston. Is the push rod removeable? You could machine a shorter replacement using say 13-8 at about H1000. In your case you are probably already pretty big on the gas port size. If you went bigger and wanted to go back to DI later you could get an adjustible block from TP555 (tp555@alltel.net) on this forum. He makes a 3 position (vent, no vent, off) that would vent off excess gas to avoid a kaboom if you want to shoot supersonic with a fat port. The vent on your GSR-35 might be too fast and/or too large to ever work since there is a big pressure difference between what you are doing and what it was designed for. I haven't even seen one close enough to know what shape it is. LWRC was talking about making one, but you'll have to buy the whole upper of course. It won't be out until 1/2 way through Hillary's first term and by then guns will be illegal.

[THE DOCTOR]

Yeah i have one of the 3 position gas blocks from tp555 it works very nice and is a first rate piece of equipment. i just went with a regular gas block on this system. You are correct in saying that the GSR unit is designed to dump a lot of gas quickly so i may have to make there holes smaller by building a bushing that goes over there gas ports or close up a couple of there gas holes and only allow a little gas out at a time. Yeah i thought about making the op rod shorter and moving the port but that will be a last resort.

Thanks for your thoughts

I will keep you posted

DOC

[kogashuko]

Any further luck with this? I am about to build an upper and can save like $150 if I buy the piston system instead of the DI system and then upgrading.