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Jaxom · Senior Member

In my small arsenal of weapons I have a Crosman 1008. Yeah, you don't have to say anything, I've already read the reviews, I would have been better off buying something different. But it's too late now, oh well.

The point of taking tuning this pistol is more of a learning lesson then anything else. I really don't expect to accomplish much. But the experience dealing with small parts and how air guns work will certainly be benficial.

Before attempting doing this I did do a search on here and across the net to see if there were any mods. Unfortunilly there isn't any. I was lucky enough to find schematics and parts lits for it though.

After disassembling the pistol, the first thing I took a look at was the barrel. This definetly will require a crowing job. Heck one side looks like it was dropped on something hard and dinged. This couldn't have happened while assembled because of how the barrel is held inside the barrel assembly. This was assembled this way!

Now my attention is one the valve assembly. First I took the bottom part off where the Co2 enters the cast body. If there's one thing I really hate about this pistol, is how hard it is to puncture the top of a cylinder. But I can't see how I can lengthen the pin that does this.

Underneath the in is the diffuser screen. Since this is just an experimental job, I'm not going to replace this when reassembling. Just to see if I can get better flow. Once the screen is removed you can see the tiny pin hole where the gas flow up into the valve chamber. I'd really like to drill this out bigger. But as of right now I don't have a small bit set, so I'm not sure what size it is, or what size to make it.

Next I took apart the top of the valve assembly by removing the rear brass plug that faces the hammer. Once this is removed you can then pop out the hard rubber washer that holds the piston, piston spring, flat mental washer and 0-ring out of the valve assembly.

This is where I could use some advice from the valve guru's here abouts. What I think would be a good tune could possibly ruin this pistol. But, since this is an experiement and this is a learning lesson, if I sacrafice this pistol to gain knowledge for work to be done on a future "keeper", all the better, right?

One thing I noticed is that the brass screw that holds the assembly together has a ridge around the edge and around where the piston extend through it. What I was thinking of doing is grinding this flat and then installing a thinner rubber seal then the one that's installed. The idea here is to make a larger chamber when the piston is pushed forward when the hammer comes down on the piston.

I'd also like to drill out the piston a bit too. There are three small ports where the piston pin becomes a hollow tube. Then of course drill out the main piston tube as well, so more gas flow through it and out the assembly.

So far, that's all I've come up with. Sorry about the long posting, I just didn't know how else to explain what I was doing. Any advice on what I'm doing or suggestions what else I could do would be appericated as well.

Thanks

Jax

Jaxom · Senior Member

18 views and no replies. I must have rambled on like a big dummy or something. Ah well. It's still been fun working on this 1008SB of mine.

Since one of my ultimate goals is to eventually buy one of the 22xx series of pistols/rifles, I've been doing alot of reading on how to mod/tune those and slowly gathering a list of which parts I would like to buy and who carries them.

One thing that I made note of is that, the longer the barrel, the faster and more accurate a gun becomes. And I'm sitting here looking at this teeny tiny 4 3/16" long barrel from my 1008SB. And I'm thinking, wouldn't it be nice if I could put a 6" or 8" long one in there?!

It might look funky, but what the heck! So long as it shoots harder and better, why not give it a whirl? Problem is, after googling through a dozen or so pages I can't find any site that sells barrels for crosman pistols.

Any suggestions on where I can find a longer barrel for this pistol???

Thanks

Jax

broommaster2000 · Moderator

You could try asking someone to make you a barrel that fits your pistol. Mr. Green

Slavia · Moderator

O.K., I'll admit to owning a 1008.

One problem with the 1008 is the repeat mechanism. There is no stop on the "cylinder" (i.e., the rotary magazine) to index rotation, so the cylinder parks itself wherever the cylinder hand leaves it. This may or may not be aligned with the barrel. You have probably noticed that it shoots most reliably when you "stop" the trigger at a certain point. This is really difficult with rapid fire, and you have probably noticed frequent failures in that mode.

Crosman made the gun with a "self alignment" feature, which is to say that the barrel fits so badly in its plastic housing that it flops around. Shake the gun and you'll hear the barrel doing its little "alignment" (not really) dance. This, plus the linkage to the magazine is all wimpy plastic parts prone to wear and breakage.

It is possible to lathe turn the outside of a replacement barrel so it fits, but you will probably need to put a healthy chamfer or "forceing cone" inside the breech end so pellets will be guided into the bore from the magazine.

Then after you have gone to the effort and expense to upgrade the barrel, you still have an absurdly complex (and plastic) double-action trigger that will never let you shoot to the barrel's potential.

You have probably also noticed that if you crank off eight rounds too fast, the last few shots are underpowered and shoot low. Every time you remove gas from the CO2 ampule, you are also removing heat energy. This means lower temperature, and therefore lower vapor pressure until your hand warms the ampule back up. Smoothing or enlarging the exhaust porting might work, but mods that increase reservoir volume will just suck heat out that much faster.

If you want to have fun shooting, leave it alone and shoot the bejeebers out of it until it breaks. If you enjoy tinkering, this will provide you with hours of enjoyable frustration.

I added my barrel after the linkage finally gave out. I breech load the pellet single-shot, and add the (empty) magazine simply as a gas seal. Then one day I bought a Marksman 2004, and I haven't looked back.

I know this is just what you wanted to hear! Still, this forum is full of folks that do things that weren't thought possible. My fondest hope is to be proven wrong when you post pictures of a 1008 "steroid" carbine.

broommaster2000 · Moderator

Am I glad that those kind of replicas are illegal here. Mr. Green

That's the great thing about prohibition. Less crap to worry about. Idea

Jaxom · Senior Member

Thanks for the advice. Especially about the barrel issue. After I posted that last night, I went on Crosman's website. Now, I don't recall where I but I remember seeing a "crosman stock barrel" being advertised for less then $20 for the 22xx series. Kinda odd if you think about it, since Crosman them selves don't sell any for less then $50.

If this was all true, I was figuring that a longer barrel that would fit the 1008 should be less then $10 or so. Because in all honesty, I'm certainly not going to invest any more then that into this piece of junk. I'm better off applying that towards buying a stock 22xx (I'm leaning towards a 2240).

I have learned alot doing this though. So I guess that's as I mentioned at the beginning of this thread is the main point of doing all this. It's also taught me patience at dealing with squirrely parts that like to go flying just because they can, normally after you've spent an hour making sure they're in the proper place! It's also taught me that using a tv stand in the living room is NOT the proper place to do these things, no matter how much I wanna watch the Cubs kicking butt across the national league.

Final note though. It would be nice to have a sticky or such with recommended tools for doing mods and tunes. While I my assortmant of tools to be quite extensive, you just never know when the right thing might just come in handy. Best example I can think of is, what is the proper tool to install or loosen those brass plugs on valves? Personally I was thinking of taking some stock sheetmetal, and making a U shape out of it, and then welding on some sort of handle.

Along those same lines. I've often heard about people replacing springs for harder/softer ones. How does one go about determining how strong a spring is, so you know what to ask for at local gunshop or hardware store?

Pie Man · Member

Hey i think you should go with the 2250. It already comes with a shoulder stock, scope (its really crappy though but its a scope) and shoots faster. I have one and love it. Mine is very accurate out to 25 or 30 yards. I have taken chipmonks to 30 yards and rabbits and squirrels out to 18 or 20. Its alot better than that 1077.

P.S. If you pray god will help you through your hard times

Jaxom · Senior Member

I understand that it has a plastic stock. But that's the problem. It's not field removable. If, as I've mentioned I add a longer barrel. with that stock I won't be able to stuff it in my back pack without it hanging out all over the place. I'm thinking along the lines of something where I can quick attach in the field.

Picture this if you will. Moding the 2250B version so it can accept bulk air from the rear like the 2250XT version does. But instead of having it angled down and being part of the stock and actually using the C02 cyclinder as the cheek rest do this.

Imagine a squar bar that comes straight down. Have some sort of conncetor so it can screw onto the modified end of the pistol to charge it. (This bar would have to be hollow) To this bar you can weld on two rods. One on top, one on the bottom leading backwards to a butt plate. In the middle between the two rods have a tapped connector the Co2 cylinder can screw into.

This way I could stuff the stock, a couple of C02 cyclinders and pistol/rifle in pack and not have to worry about having it hang out... (Ever get stuck in thick brush hauling a rifle or fishing pole??? Or like I use to do, metal detecting, oy! it's a pain in the you know whats!!!)

I'd love to build this, but my welder can't do aluminium. I don't have a lathe to do the tap, die stuff. And well most importantly, I don't have the pistol to experiment with!

I did just whip up a funky looking diagram of what I'm talking about, but I don't have photobucket to post it. AND photobucket is down for maintence. [/img]