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radar · Silver Status Member

Thanks Todd. Good luck, as I am just experimenting here. I don't know what I'm doing yet. Smile

Instead of the tedious polishing, today I decided to fix the breech by giving it a “Cardew radius.”
I took a ¼” brass rod (which every shop out to have—got it at the hardware store) and turned it down to .174” to make a pilot. Once again, I have to be the good forum citizen here, and say not to put files on spinning things unless you know what you are doing. Files like to snag and fly and pull fingers into the spinning parts—OK?

I then slotted it with a Dremmel tool, clear through, so I could solder in a piece of utility knife blade. The blade was shaped to make a single blade radius cutter, and the pilot was oiled so it would turn as it was intentionally pretty tight in the chamber to keep things nice and square. A tap handle was used to turn it.

That’s better, I think.

Before:

radar · Silver Status Member

The mainspring is done. The ends were squared up using a vee block clamped at 90° to the grinding wheel and slowly rotated by hand while light pressure was applied. Got to go slow or it heats up and ruins the temper of the steel. Polished inside and out with a 3M "red" metal conditioning pad followed by 0000 steel wool. Dremeled to de-burr the cut ends and finally re-blued and lightly oiled to prevent rust. Later I will wipe most of the oil off and apply anti-vibration tar and a little moly-paste lube.

I like to see 2/3 to 3/4 of the circumference of the ends making contact with the spring spacer and top hat so that the spring has good footing to push straight off from them without cocking sideways.

Before:

After:

SMP · Silver Status Member

Nice job mister

I'll give that Thumb Up!

Try to find two thin flats for either end of the spring. If they are polished really well and hardened they will act as a torrington bearing allowing the spring to rotate naturally as it expands. I buy hardened shim washers from the local fastener store. or gr8's and harden them myself

It's minor but why not Mr. Green

radar · Silver Status Member

Thank ya.

Slavia · Moderator

Looks good so far. The spring compressor looks great. I agree with SMP about the washers. If the spring can't spin it will kink, which causes extra friction and vibration when the gun discharges. Adding too much risks coil bind and a harsher firing cycle, but I think you removed enough material (when squaring the ends) that you've created some "wiggle room" for washers.

How does the spring guide fit inside the spring?

radar · Silver Status Member

SMP · Silver Status Member

Very nice job all around Rob. That thing should just purrr

I like the innovative use of the rust preventative. I use a non conventional super sticky lube as well called PJ 1 Black Label Chain Lube

Super sticky super slippery moly based sludge...but smells like A$$ when its fresh.

http://www.motorcycle-superstore.com/2/9/197/12508/ITEM/PJ1-Black-Label-Chain-Lube.aspx

Whats the plan for the barrel?
recrowning
choking
a nice hand lap?

Hmmmm?

radar · Silver Status Member

Thanks! And for the link, too. I might try that out, but so far I'm pleased with the spray-on stuff. We'll see if it works out.
I'm going to carbine the barrel, recrown of course. Lap it, and muzzle brake it. Also going to remove the iron (read plastic) sights and fill the holes.

Then the stock. I was thinking airbrush camo, but now I'm leaning to a richer, dark, high gloss--Old Skool.

Edit: Oh yeah THAT kind of chain lube---yes, I use similar (JB I think) on the RWS, because I can shoot a little in the cocking groove on the spring without disassembling it, which I never have yet. Good for lubing and it quieted it down nicely.

This rustproof stuff is like warm wax when dry. Never hardens, always tacky.

radar · Silver Status Member

Today the barrel was bobbed by 5 ½ inches and ground square. You might see the reference mark just behind the new muzzle. That was made with a pipe cutter—just enough to make a groove mark that wraps 360º around the barrel. That gives a nice point to grind to that is square to the axis. Not too tight there on the cutter as I didn’t want to crimp the barrel inward.

I set up very carfully here. Even though I’m going round and round with the barrel, it needed to be pretty exactly perpendicular to the axis, in both X and Y, and therefore to the square I use for a vee-groove guide.

It’s coming along. The outside chamfer is 45º.

A little gentle polishing…

3/8” ball bearing—actually slingshot ammo chucked into my cheapo drill press. It did take a few tries to get it so the sprues weren’t on the prongs of the chuck so that it didn’t wobble. Smeared with fine-grade automotive valve grinding compound, it was used to finish the inside bevel of the muzzle. I could have used a hand drill just as well.

That finished, I cleaned the bore very well and ran some Flitz metal polish through it. I used cottom swabs to check for burrs. Finding none, I went ahead and made a couple detents for the set screws that will attach the muzzle brake.

Now to fill the sight screw holes. They were cleaned out with Birchwood-Casey rust and blueing remover, washed and dried. I used 450ºF acid core solder and a Mapp gas torch to fill the holes over level. Using a pin punch, I gave them a little swat to obturate any hidden pinholes in the solder into the screw threads.

After bit of filing with gentle, curving strokes.

A bit of polish with the good old 3M red metal finishing pad. The solder can be melted back out and a tap to clean the thread, should I ever want to re-install open sights.

Cold Blued and oil rubbed.

I put the breech seal back in (had to be removed for heating the breech for solder) and reassembled the whole thing with a bit of moly paste on the moving parts.

Now I will take a break from the metal work and do something about this ######-yellow stock. This will give me time to think about a muzzle brake fabrication or purchase, and I am also waiting for the arrival of the upgraded, fully adjustable trigger blade from Airguns of Arizona. The trigger can be installed and adjusted without disassembling the power plant again. It only has to be taken out of the stock.

TheAznInvazn · Member

Very nice project you have going!
Hopefully the project that I have in mind can live up to the standards of this forum and all of it's awesome modifiers

garththomas · Veteran Member

Great job on the pics and discription, I am suprised on how rough and messy it looks. I wish I had a camera when I took my QB57 apart, it was in a lot better shape than that. Keep it coming.

SMP · Silver Status Member

Looks great Radar

I'm really interested to see what numbers that bobbed barrel puts up.

Your right though that's the most yellow quest stock I've ever seen

AirGunEric · Site Admin

The last few months Crosman was putting out the Quest (before changing it to the "Optimus" they were pumping out these awful yellow-orange stocks consistently. It's almost as though someone was intentionally making them as ugly as possible so that when the more-appropriately colored Optimus came out, people would be all over it.

Either way- good work on the rifle, Radar.

radar · Silver Status Member

Thanks guys. I'm just playing with it because tools keep me sane. It's kind of fun keeping a running post too.

Sean, I am interested in any power changes too, but everybody says you get all your pellet velocity in about 6" of a springer rifle. We'll see won't we? Very Happy

I got that Remington Vantage 1200 that's the same as this except for the stock. I mean all the part numbers except the stock are the same numbers from Crosman's parts lists. I think the fit and finish of the metal bits wer better on the Vantage, and I don't know whether or not they have a higher QC/finish requirement because they are getting more than half again the price, or it was just made on a good day.

Anyway, where was I? Oh yeah, the Vantage ought to be a good velocity standard to compare to.

SMP · Silver Status Member

Rob

One thing I have noticed about the offshore crosman stocks is when they are dye stained the traditional way they always have that cheap wood thats been stained look to them.

Just a suggestion but I would hit the stock with several coats of prestain conditioner(also available as "natural") to enhance the depth. Then I would use pigmented urethane to develop the colour(ie polyshades)

Once you have the colour you want add any additional topcoats with clear high gloss then rub the finish to the luster you want.