My first B1 rifle - the darn thing works!

[gloob]

I finally did it. I bought the cheapest and possibly worst air rifle that has ever been made... at least which has been made in excess of the 10's of thousands.

Out of the box, the front sight had already fallen out of the dovetail. And the barrel had significant lateral play. Doh! Many cheap springers into this hobby, I have come to believe that as long as the rifle locks up tight, I can get it to shoot. So I had low hopes to start.

Oil was oozing out of it, everywhere. And the "clear" breech seal is permanently tinted orange with surface rust. But despite that, it only dieseled for the first 10 or so shots. Stuck a red dot on it and the accuracy was not good, yet.

Power is supposed to be around 500 fps. I don't have a chronograph, but my penetration testing puts it at around 550 fps with 7.5 grain pellets.

After just one day, I have it grouping great.

My mods/repairs:
Firstly, I took the barrel/breech out and stuck the end of the cylinder in a vice and gave it a good squeeze, until I could just barely stuff the breech back in after debur/chamfer of the sharp edges. Didn't even bother padding the vice, because the finishing on this rifle is laughable, anyway. But this took out all the lateral play in lockup!

I peened the dovetails for the front sight with a small tack hammer. Success! I started the front sight in with a vice, and finished tapping it in with a brass rod and hammer. It holds tight, now.

The rear sight has a lot of play. I wedged a brass shim in it, so it doesn't move, at all.

The trigger was painful. High break weight is part of it. But it also has too much curve to it. I straightened out the curve with a vice. And it's miles better. The weight is completely manageable, and it breaks cleanly with no creep.

And that's about it. This rifle shoots great and has just slightly more power than I expected. It should be plenty good for rats, and it's now my only air rifle with steel open sights! This is pretty much what I wanted when I bought the (new) Hatsan Alpha. I can easily hit pieces of gravel at 15 yards with the open sights!

[gloob]

Well, my previous experience with barrel length still holds true for me. I really wanted this rifle to be the exception, because i want to keep the iron sights. But it is not. The barrel is too long!

After getting used to the heavy trigger, and now that the stock screws are mostly settled, I found the accuracy was not quite all there.
I shortened the 16" barrel down to 12", and it's definitely more accurate with 7.5 grain pellets, now. It'll take more time to figure out how accurate it is, due to the trigger. But I'm already starting to trust it!

I even took the time to reinstall the front sight. 40 minutes with a Dremel and files, and I made my first dovetail in a rifle barrel. Even with the shorter sight radius, it shoots better!
 

[gloob]

I figured I could remove about a half inch more off the barrel from where I put the front sight. And it's now spraying like a shotgun! I may have found a loose spot in the bore or maybe I just hit a sweet spot for bad vibrations?

I can't shorten it anymore without losing all that work reinstalling the sight.    Maybe I'll try a muzzle weight, though.



 

[lefteyeshot]

The B1, 2 and 3's can be a lot of cheap fun. But the old B2's with the barrel latch are impossible to find new.

One B2 I had way back that was a pretty good shooter. I added a scope, slip over rubber recoil pad and stretch nylon cheek rest, barrel weight and knocked the open sights off.

[gloob]

Thanks. It might be shooter, yet.

I think what happened is the stock screw in front of the trigger guard must have come loose, when I shortened it the second time. Vibrations from the bandsaw, perhaps. It had never came loose before, and I had stopped checking it!

But... I didn't notice until I had given up and cut it down some more. I have the barrel at 9" now, and it's grouping, again. Of course it's too short for open sights, now, unless I add a shroud!

Still no real muzzle blast at 9". Still penetrating one side of a gatorade bottle, like it did out the box. Oh, well. I might shorten it some more and add that shroud and front sight.

[19Sheridan57]

   Those were a " $20  Flea Market Staple " for a long time.

[Madd Hatter]

I believe in the book trigger to muzzle stated that around 9 inch barrel length worked best,at least for the springer they did their testing on. It's been a long time since I read it so could be wrong.

[gloob]

Madd Hatter, After reading Cardew's book, my takeaway was that the single most important thing to be concerned about regarding accuracy is matching barrel length to velocity. Then overall weight of the rifle.

The lower velocity rifles usually have too long of a barrel. I have many/most of the springer rifles I know of, now, in the 450-550 fps range. I've shortened the barrel on all of them, with massive gains.

I've found many cheap full power springers also have too long a barrel. They must be that long in order to reduce cocking force and/or maybe to shoot light weight pellets, accurately?

I've got the barrel down to 8", and it's appearing to be consistent, now. Closer to one-holing at close range, rather than cloverleafing. I'm kinda torn on whether to spend the effort to add a shroud. I'm not a trigger snob, but this one might be beyond my limit!

[lefteyeshot]

My Mendoza rifles have long barrels but only 9-10 inches is rifles. The rest is bored out bigger.

[gloob]

The HK97 and TX200/Pro Sport rifles also have 9" barrels with extended shrouds.

I wish I could bore out a barrel like that, to leave the front sight on. That must be a PITA to debur! I'd also like to bore out a barrel to try to make a shotgun, someday. But I hope to have an inaccurate springer for that. And so far, I just keep making cheap rifles into shooters. I need to stop doing that, because I have too many redundant rifles.
 

The lockup gave me some concern, when it got a bit crunchy for a bit and seemed to stop just shy of full lock for a spell. Horrible vertical stringing to go along with the incident. But whatever it was, it seems to have settled in after smacking it closed good and hard a few times.

I mustered up the energy to install a nice long, heavy shroud onto this rifle. Even though I've done the exact same thing on several rifles by now, I'm still surprised at how much this reduces the shock. And reduces the perceived noise. And by how much better the stock screws stay put. And by how much better the rifle holds on target. This one wasn't particularly hold sensitive to begin with, but adding that weight has done miracles for hold sensitivity on other guns. I swear the trigger feels lighter, even. I suppose a 20 lb trigger wouldn't feel that bad on a 50 lb gun. As long as the gun doesn't move when you crank on it?

And my verdict is in. I have another shooter.

[gloob]

Pics!

Shroud of 1" steel tube, 30ish thousandths thickness.


New front sight, dovetailed piece of 1/8" brass, tapped in with a hammer. Solid!


I have learned to keep a piece of your cutoff barrel. Helps with making the bushings for the shroud. Stick a piece of brass rod into a drill, and file the end until it sticks into the bore. Now you have a mandrel for drill-turning the bushings.

[gloob]

Well, this B1 is now pretty much my favorite rifle. I'm not sure when it happened, but somewhere along the way of over 1500 shots, the trigger got good. When I realized, I tried to pay close attention to how it breaks. It took 3 shots for the weight and break to even register in my brain. I would shoot it. Hit my mark. And then try to remember what the trigger felt like, and I would just draw a blank!

The trigger just breaks when I want it to. It breaks cleanly. Probably 5 lbs. And the shot just goes where it's supposed to. It's probably one of the best triggers I have, now. And it's far, far from the worst!



The lacquer finish was too slick for my liking. And I wanted to do some reshaping of the grip, too. So I stripped the finish, simply using coarse sandpaper by hand.

The finish is pure tung oil. Linseed darkens a bit more, but I couldn't find it at the time. So a blonde she is.

My shroud bushings were a hair too small, on my first try. The shroud developed just a slightest detectable wiggle/play. I remade them to a proper tight fit on the front bushing and interference on the rear, requiring hammering it home to fully seat.

[lefteyeshot]

You have a nice little gun there.

[gloob]

Safety update:

Trigger just kept getting better. It's probably between 2 and 3 lbs, now. But I discovered the gun will consistently fire if I bump the butt on the ground! Definitely not a dropsafe design.

I'm not sure this is a big consideration with air rifles. But I tried it on my other regular shooters, and nothing happens.

[gloob]

Worse. I got the gun to fire even by slamming the barrel closed, a few times.

I am sure I precipitated wear on the sear interface by installing a trigger stop that was too aggressive. But after tearing it down to take a look, it's really nothing to see. The sear hook and notch are both in good shape. Good and hard steel that skates a file and shows no discernable wear through use. So I probably just accelerated the wear-in on the top of the cylinder and piston, opposite of the sear interface.

I ground the interfacing edges a little, taking out a tiny bit of the factory radius on the edges, to make the engagement slightly longer/sharper. I couldn't get it to fire when slamming the barrel closed, anymore. But it still bump fires every time, with a hard enough hit to the butt. Harder than before, at least. I think the long length of the trigger just makes this a reality, that inertia can make it pull.

Trigger break is still light and clean.

I removed the trigger stop. The trigger has to go nearly halfway back before there's no interference/friction, at all. So I don't think this gun can practically use a trigger stop. I've never tried putting one on any other springer, because this is the only one that breaks clean rather than rolling off, anyhow. So I wouldn't be surprised if this is the norm.

I take that back. I have a trigger stop on my Trevox. But it's a weird and really long and heavy trigger. There's still a ton of follow through, just less than the 2 tons it started with.

[gloob]

Heads up. If your B1 has a gigantic bur on the piston, right where the cocking arm pushes against it, leave it there.

I went ahead and removed it. Eventually, the cocking arm slipped right under the piston. There's a wild amount of play between the piston and the cylinder, allowing that to occur. And the giant bur that was on there, originally, was a work of art. No clue how one makes a bur that large and functional (probably a good clue I should have left it alone).

I figured it was a 5 minute job to tack weld a small button/bump onto the top side of the piston directly opposite of the cocking arm interface. That should take out enough play so the cocking arm can't slip by. Proceeded to burn a hole right through the piston wall. I got enough material on there for the button. A couple minutes of filing and fitting, and it was good. But I also left enough weld on the inside of the piston that the spring wouldn't fit back in. So the job turned into half an hour of sanding the inside of the piston with PSA and a 3/4 tube.

So far so good. The bump also increases the sear engagement just a tad. Trigger is still crisp, but the break weight went back up to 4-5 lbs. The rifle still bumpfires like clockwork.

[DanD]

This is a fun adventure to follow. Thanks for taking the time to post it all.

[gloob]

Thanks.
[Imgur]()

Here's an updated picture.

I added a flashlight. A scope ring obviously fits perfectly on a 1" shroud. I just epoxied a piece of picatinny rail to an 8 dollar flashlight.

The scope is a package Centerpoint that came with a Crosman rifle. 3-9 x 32. Fixed parallax, but it's adjustable with the right spanner. I have it set to 15 yards. It's useable to about 25 yards, max, which is fine. That's as far as I can hit anything small enough to be shot at with a 550 fps rifle... in my case all I care about are rats. There was a screw on the zoom ring. I removed it and replaced it with a brass throw lever.

The scope already lost zero twice. But there's a bit of droop on the rifle, and after messing with the turrets, the scope still works. I am on my second attempt at shimming, to get it where it will keep zero. So far so good. It held zero on a much sharper recoiling rifle for years, so I believe it should hold if I shim it straight enough.

The open sights work a treat. They're spot on, even though the only windage adjustability I have is which side I put the shim on the rear sight, and a file. But I shoot way better with a scope, and this particular scope is always ready to go from 5 to 25, with no fiddling.

[Toxylon]

In the early 90's I bought a B1 on a whim. The gun rapidly descended into an ever-more-precarious firerer (I know that's not a word), where ultimately just slamming the barrel shut would make the gun go off.

The B1 had such minimal power (I'm guessing the .177's left the barrel at around 200 fps or so) that no harm was done, even if the thing was as unsafe as they come.

Trash can called, and the B1 answered.

[gloob]

Yeah, it was the piston wearing in that reduced the sear engagement, on mine. It's a pretty easy fix. Even if you didn't have a welder, you could solder a piece of sheet metal onto the pistol skirt. Or drill and tap and insert a machine screw, and grind it down.