.22cal barrels

[zenonine]

Is the .22cal Discovery subject to the "Crosman barrel lottery" as I've read the .22 cal Marauder is ?

[nervoustrigger]

Different barrel.  One marked difference is the Marauder barrel is choked, the Discovery not.   Neither is very highly regarded on the average but they can be very good if you have the means to clean up the trouble spots and take the time to find a pellet the barrel really likes.  If you have no interest in such things, get someone to machine you a Lothar Walther blank

[Bicycleman]

Randy, my Discovery .22 was good out of the box.  I did NOTHING to it after the first cleaning.  Head shots on squirrels is no problem.

[Ribbonstone]

Yes...as is every barrel from every maker, just that other brands have different (better) odds.

Also depends on what your standards are.  Good enough to kill squirrels at 50-60 yards or good enough to win matches at 50-60yards?

[Deckard1973]

Different barrel.  One marked difference is the Marauder barrel is choked, the Discovery not.   Neither is very highly regarded on the average but they can be very good if you have the means to clean up the trouble spots and take the time to find a pellet the barrel really likes.  If you have no interest in such things, get someone to machine you a Lothar Walther blank

When you say " . . .  they can be very good if you have the means to clean up the trouble spots . . ." are you referring to lapping and polishing the barrels?  Or just polishing? 

Thank you for your input!

[K.O.]

Polishing the Leade if needed and making sure you do not have a sharp transition to the rifling,knocking down a burr at the transfer port if needed, new crown if needed...

there where some .22 barrels that when they used a crowning tool it messed up some of the rifling at the end of the barrel those needed exchanged or shortened... I got one of those but I had planned on shortening any ways so...

I got one with some strait very shallow grooving/scratching that polished out...

Me I give mine a quick fire lapping also...

Some are bad but some shoot very well... considering the price they can be amazingly accurate...

the biggest problem imo is the thin walls invite harmonic probs but under about 16-20 fpe..

[nervoustrigger]

....are you referring to lapping and polishing the barrels?  Or just polishing? 

Kirby pretty well summed it up.  The big things are those that can really chew up the pellet...a burr at the barrel port, a sharp transition to the rifling, or a burr at the crown where the pellet emerges into the world.  Polishing the bore is worthwhile also but it tends to have less of an effect on accuracy as it does how many shots you can get before cleaning is necessary.

The first thing I like to do before any work takes place is to push 3 or 4 different pellets through.  You may be surprised how easy it is to feel trouble spots.

Here's a write up I did a while back if you are interested.  Somewhat lengthy but the techniques described are well within the capabilities of any mechanically inclined person.  That is, you don't have to be a machinist. 
http://www.gatewaytoairguns.org/GTA/index.php?topic=74149.msg707998#msg707998

The results are excellent, so say these Chinese barrels:

QB78 HPA:


QB79 HPA:


Crosman 1389 pumper (with the suspect factory barrel band):

[Ribbonstone]

This is actually a very good Disco barrel.  Shoots great short range (20yard) groups.



Looking at these, if you didn’t measure them, you might think “great…”one hole” groups.  Yeah…but they’re kind of oblong/stretched out “one holes”.

Move out to 60 yards, and the groups grow a bit disproportionately larger (they are larger than 3X the 20 yard groups).



That’s certainly not “one hole” grouping, but it is 60 yards.

So, from looking at the real-world results of averages. I will call this a 50 yard rifle (as likely at 50 yards, they’d stay inside 1” most of the time).

But we have several problems with air gunners and groups:

1. Could cherry-pick the best group shot, ignore the rest as if they didn’t count, and call that the accuracy of the rifle. Realize that the shooting-gods do occasionally toss the trigger monkey a banana, so one great group is likely just a random happening.

In just the above tests, the air guns gods tossed this trigger money a .9MOA 20 yard group as a banana and a 1.26MOA group at 60 yards.  Then they tossed a 1.9MOA group at 60 yards and a 1.5MOA group at 20 yards.    You’d be just as justified to call it a 1.9MOA rifle as a 1.26.

2. Second problem is extrapolating long range groups from short range groups.  They don’t just double with doubling the range, then MORE than double. Wind has a cumulative effect.

3.The little variations in speed that make no real difference at short range DO make a difference at longer range. You really won’t notice a 4% velocity change at 20 yards, but you will notice it at 60. 

4. It’s a lot harder to get the group adjusted to land on-target at longer range than it is at shorter range. Know it makes no difference to group-shooting, but if you ever want to actually hit what you aim at, are going to have to get POI and POA together.


So…considering the power of the rifle, the accuracy of a good Crosman .22 barrel, and NOT just picking the best groups shot, consider this a 50yard rifle on live game….which suits me just fine.

On tin cans and plinking objects like that, shoot at them as far away as you can see them. It’s not the hits or the total misses that bug me, it’s wounding a critter that does.  Plink to your hearts content at paper targets, tin cans, or paintballs at whatever range you care to.

[Deckard1973]

Thank you gents for the info!

Will look into it and if I give it a go make a post and credit accordingly. 

[tracker1955]

I did find on my Disco that a second barrel band near the muzzle made a big difference in tightening up the groups out past 30-40 yrds.

[zenonine]

Thanks for the comments. They served as a wake up call: I have 4 air rifles, 2 of which I attempted to improve, a Gamo Shadow 1000 I was given and tuned with a kit from ARH and installed an aftermarket trigger BEFORE I discovered a scope could not be mounted account no scope stop and a gunsmith told me the dovetail grooves weren't deep enough to hold a mount. He wanted $ 50 to drill a scope stop hole. Also have an Umarex Octane I resealed and added a trigger component. Another waste of money. I really don't like working with my hands and was foolish to attempt making a silk purse of of a sow's ear. You get what you pay for. The most accurate gun - which is most important, is an HW 30S with 5k rounds through it. All I've done is adjust the trigger. Also have a 12fpe 2289 survival rifle. It's accurate enough. The comments about airgunners and accuracy was spot on. While reading and viewing targets on this forum I sometimes wonder if the poster actually believes the reader will believe the group sizes. I also sometimes think possible, yes, probable, no. So I'll just continue to shoot the HW, ( and not post any targets) and save for another more powerful HW capable of shooting one inch groups at 50 yards consistently.