Jaymo, Bam50/51 stuff

[spysir]

I didnt mean to hijack the thread below this so I thought I should move here? old thread:
http://www.gatewaytoairguns.com/airguns/forums/thread-view.asp?tid=23137&mid=183938#M183938
 Yes it is a Purpleheart stock :


 "Maybe the front trigger guard screw needs to be shortened a wee bit."  Did you note the nut fits one way? Dish on one side or a flat or something I cant quite recall right now but I am sure I am right about that and it "can" cause a problem.
 "polish the hammer, hammer weight" like a mirror would be good.
"Do you recommend honing the inside of the tube" just remove burrs which will mostly be in the slot screw #26 chewed up. I did use a White sanding pad on a dowel just to remove the dried gunk.
"Have you tried using a lighter valve spring to get more power" to get to 40fpe I used the stock hammer & valve spring with 2mm cut offf the front of the hammer (striker) and the adjustment screw flush, that's all there is to 40fpe.
"What material did you use for your transfer port? " Brass TP's with shortened polished hammer:

 Using one of BigEd's valve stems will up the power due to better flow :


 I Ed sells them for around $10.00 ?

 John

[Jaymo]

Sweet. I'm really starting to get back into my B50 now. I bought it to hunt squirrels. It's a total waste of money if I don't address the minor issues that add up to major headaches. There's obviously plenty of power potential in that design.  The increased velocity, coupled with the total lack of recoil, makes it a lot easier to get good hits on squirrels and rabbits. I followed one squirrel today for about 10 minutes(with the scope on my B30) because it wouldn't stop for anything. It was moving around my yard and as soon as it stopped, if moved again. Let that one go, never could get a good shot.
I was thinking about chucking the hammer in the lathe and facing a couple of mm off the front, in order to give a little more travel. Good to know someone else has done so and had good results.
I'll have to dig out the bench grinder/buffing wheels/polishing compound tomorrow. Or maybe just chuck the hammer in the lathe, run it at high speed, and use the Dremel with a felt bob and some red and white rouge. I thought about honing the inside of the hammer and polishing the hammer weight and spring ends. Just 'cuz.
I need to polish the screw that goes into the bolt and cocks the hammer. I also need to polish the ways it travels in in the breech, they're a little rough. While I'm at it, I'll polish the bolt, it's raceway, and the breech.

What TP hole diameter did you use to get 40 fpe? Stock,  or larger?

That purple heart stock is gorgeous. Won't work for me though. I'm a southpaw.
I'm really glad you're still around. Not many people seem to be talking about the B50 since the Disco came out, and I obviously need guidance on mine.

I think I need a BigEd shroud, riser, shroud band, and of course, that valve stem.

[patton123]

What size tank are u using and with what adapter?

[Jaymo]

I have a couple of 50 cubic foot scuba tanks and a valve from the dive shop. I use the tanks to bulk fill to 2,000 psi and then pump the rest of the way up to 3,000.

[Jaymo]

Got everything back together today. Big improvement. Thing is, it's a monster at 2,500 psi, but it's weak at 3,000 psi. Need to get a spare valve assembly to mod. Also going to try a little weaker valve spring. Not much weaker, just a bit. I think I'm going to polish the inside of the tube, where the hammer slides, mirror smooth, too. Gonna have to make a lap to polish it, because the cocking slot precludes me using a brake cyl hone in it.
Also thinking about making a new hammer weight/spring guide that's longer and heavier. While I'm at it, I'll drill/bore the rear tube cap a little deeper to accommodate it.
If I had a disc of tungsten or mallory metal the same diameter as the hammer weight, I'd just install that inside the hammer and weight.
Thought about drilling out the air holes in the hammer, to see if that helps.

There's some serious volume increase potential in that valve. The front valve plug only goes 1/3 of the way into the threads in the valve body. The valve body can be bored out from that point back.
Got a lot of ideas for this puppy. Gonna need to buy a spare drive belt for the minilathe.

[patton123]

Hi Jeremy, I read your response on the scuba tanks. I like the idea of filling the gun up with a scuba tank, then rest with a pump. I have a hill pump, but for some reason it doesn't work.  Maybe its my connection to the rifle. Anyways, when you have time,  can you post a pic on the connection setup of your pump to the rifle.

Thanks

[Jaymo]

Sure thing. My pump setup is simple. It consists of the pump, the hose that came with the pump, and an extension hose I had made up at a local hydraulic shop attached to the end of the factory hose. The factory hoses are too short for my tastes. So I now have double the length of the factory hose. On the end of the extension hose(just a braided stainless steel hose), I have a female QD fitting that connects directly to the male QD fitting on the air tube of my B50.

I replaced the fill port on my Sam Yang with a male QD fitting from BGMF Airguns dot com. It's the same size as the QD fitting on my BAM B50. That way, I don't have to change out fittings/probes to go from one to the other. Just connect the tank/pump and start filling.
I do need to put a longer hose on my refill clamp for my tank. I just have a short hose with a 90 degree elbow fitting and a female QD fitting.

The reason I don't fill to 3,000 psi with the tank is because I used to do just that. 3 or 4 fills and you no longer have 3,000 psi available to fill the gun. I have 2 tanks, both are 50 cu ft tanks that I got used with a fresh hydro from the scuba shop for $60.00 each. He even filled them for no cost when I bought them.
So, I fill to 2,000 or 2,500 psi and then pump the rest of the way.
A compressor would be the way to go if I had the money for one. But I don't.

[Jaymo]

Got distracted by my Benji HB20 pistol and my wife's Crosman 760. Both are a lot harder to pump than they need to be. My wife's 760 is a LOT harder to pump than my son's 760. I had a spare 760 valve and modded it for easy pumping. You now have to cock it or just pull the bolt back to the first click before pumping it, but it's a lot easier to pump, and will dump 15 pumps. Haven't gotten the Benji back together yet. I plan on doing more yet to them both.
I wanna see just how much power I can squeeze out of this Benji.It's valve is HUGE compared to a 760, 1377, or 2100 valve. Now that I've replaced the valve spring with one about 1/2 as stiff as the factory spring, and bored out the valve some,  I plan on getting noticeably better performance than stock.
 Then it's on to my 1377, 392, QBs, 2100, B5-10, and who knows what. I really like working on these CO2/pneumatics. I have 2 lathes, 1 mill/drill, 1 mill, 1 shaper, 1 drill press, 5 bench grinders, 1 disc/belt sander, 4 arc welders, 1 O/A torch set, 1 Dremel, and 2 electric die grinders. That's not to mention hand tools, hand held power tools, and woodworking bench and handheld power tools. Plus I have a customer who wants to sell me a Series 1 J-head Bridgeport with power X-feed and a DRO for less than a grand.(don't have the money or room for the Bridgy, yet).
Plus there's the free machining brass hex rod and all the different sizes of Delrin rod I have. I'm ready to get back to making custom valve parts.
Now, if I only had a brain I'd be dangerous.