Another sloppy barrel??

Another sloppy barrel??

Joined: October 5th, 2006, 3:26 am

October 9th, 2008, 1:46 pm #1

Finally got to spend some time sighting in my new .22 Disco. Really wanted to use Premiers but they can't hit the broad side of a barn!

At 35 yards, four groups ranged from 3" to 3.5". Out of desperation, switched to JSB Express, and the group sizes shrunk to .68" to .9"!!!. I know pellet choice has an effect but this was dramatic.

I suspect it's a sloppy large barrel where the CP's thick hard skirt can't grip the rifling. The JSB has a very thin skirt and can blow out to the barrel ID. Time to shoot a few into the pool and examine the recovered pellets. I'll pull the barrel later and try pushing a few pellets through to get a feel for the fit.

Pity the poor unknowing fool who buys this gun and some good Crosman pellets and has to struggle with this kind of performance. Crosman......you need to tighten up the QA a bit....
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Joined: August 19th, 2007, 8:44 pm

October 9th, 2008, 2:13 pm #2

Wow! I would send that one back if possible. Actually I'd address Crosman directly. Even the almost 1" group at only 35yds., is unsatisfactory.
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Joined: May 25th, 2008, 4:38 am

October 9th, 2008, 3:24 pm #3

or just re-crown the barrel...

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Joined: March 11th, 2008, 2:17 pm

October 9th, 2008, 7:56 pm #4

Finally got to spend some time sighting in my new .22 Disco. Really wanted to use Premiers but they can't hit the broad side of a barn!

At 35 yards, four groups ranged from 3" to 3.5". Out of desperation, switched to JSB Express, and the group sizes shrunk to .68" to .9"!!!. I know pellet choice has an effect but this was dramatic.

I suspect it's a sloppy large barrel where the CP's thick hard skirt can't grip the rifling. The JSB has a very thin skirt and can blow out to the barrel ID. Time to shoot a few into the pool and examine the recovered pellets. I'll pull the barrel later and try pushing a few pellets through to get a feel for the fit.

Pity the poor unknowing fool who buys this gun and some good Crosman pellets and has to struggle with this kind of performance. Crosman......you need to tighten up the QA a bit....
Not all airguns have the best accuracy with crosman premiers. This is why most shooters with a several airguns will frequently stock a variety of pellets. In general I find that .22 JSB Jumbo's are more accurate than CPs in most of my airguns. Your results are not out of the ordinary.

However crosman does have some fairly loose specs for their barrels. I had one disco barrel shooting 1/8" JSB groups at 15 yards and another disco barrel shooting 5/8" at the same distance on the same gun. After a checking the crown, I noticed that the bore was larger which cause shallower rifling and loose pellets.

I ordered 3 more .22 disco barrels to see if I get another good one. If not I am going to return them and order a L/W choked barrel.
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Joined: November 17th, 2006, 3:51 am

October 10th, 2008, 12:30 am #5

Finally got to spend some time sighting in my new .22 Disco. Really wanted to use Premiers but they can't hit the broad side of a barn!

At 35 yards, four groups ranged from 3" to 3.5". Out of desperation, switched to JSB Express, and the group sizes shrunk to .68" to .9"!!!. I know pellet choice has an effect but this was dramatic.

I suspect it's a sloppy large barrel where the CP's thick hard skirt can't grip the rifling. The JSB has a very thin skirt and can blow out to the barrel ID. Time to shoot a few into the pool and examine the recovered pellets. I'll pull the barrel later and try pushing a few pellets through to get a feel for the fit.

Pity the poor unknowing fool who buys this gun and some good Crosman pellets and has to struggle with this kind of performance. Crosman......you need to tighten up the QA a bit....
...not a whole lot to get upset about. However, while .68" and .9" are a good sign, it should do better. Would be nice to be able to use the pellets made by the barrel's maker, but that's often not the way it goes.

They are standard production barrels that sell for something like $15-$16. Have put 2260 barrels on for some testing; no problems. Can fight with the company and get a new barrel...or can order a new barrel and put it on yourself...either way it's just another entry into the barrel-lottery.
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Joined: May 25th, 2008, 4:38 am

October 10th, 2008, 3:57 am #6

Finally got to spend some time sighting in my new .22 Disco. Really wanted to use Premiers but they can't hit the broad side of a barn!

At 35 yards, four groups ranged from 3" to 3.5". Out of desperation, switched to JSB Express, and the group sizes shrunk to .68" to .9"!!!. I know pellet choice has an effect but this was dramatic.

I suspect it's a sloppy large barrel where the CP's thick hard skirt can't grip the rifling. The JSB has a very thin skirt and can blow out to the barrel ID. Time to shoot a few into the pool and examine the recovered pellets. I'll pull the barrel later and try pushing a few pellets through to get a feel for the fit.

Pity the poor unknowing fool who buys this gun and some good Crosman pellets and has to struggle with this kind of performance. Crosman......you need to tighten up the QA a bit....
...to improve on factory guns...like barrels for instance...I bought my Disco from a TUNER....it shoots great...and I used three different pellets on the chrony...only difference was a slight variance of power...but accuracy was there...

Best pellet was JSB Jumbo Express,by the way...never tried Crosman's...but did RWS Super Domes and Benjamin's...
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Joined: October 5th, 2006, 3:26 am

October 11th, 2008, 7:45 pm #7

you don't have to buy from a tuner....but you take your chances. My .177 Disco shoots great. Crosman asked no questions and offered to send a new one. I suspect they monitor this forum and/or know about their QA issues.

Along the same lines....not only does this barrel perform poorly, it also does something I've not experienced before. I may be a technique problem on my part, but, it will make multiple groups. That is, out of, say 8 shots, two separate groups will materialize. And the groups will be really tight. If someone knows its the shooters problem, please tell me what it is.
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Joined: May 25th, 2008, 4:38 am

October 12th, 2008, 2:32 am #8

...but apparent the barrel tolerances affect accuracy/power from what I have read across several forums...that is not a negative on Crosman..because this Discovery is a very good product for the price....just an observation from video chrony data published on some airgun sites( Pyramid Air & Airguns of Arizona)and user comments with stock Disco's across the forums..

If you watch both videos you will see the difference in power...814 vs 843 fps both using 14.3 gr pellets..now one could blame the pellets,but reading forums re same rifle in .22 caliber suggests barrel tolerances from the factory...not necessarily a QA issue..

Last edited by richwoods on October 12th, 2008, 2:35 am, edited 1 time in total.
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Joined: October 5th, 2006, 3:26 am

October 12th, 2008, 3:20 am #9

First, let me say that this is an excellent product for the price. I am very happy with the Disco, probably because a little TLC rewards one with an amazingly competitive rifle.

But, I can't imagine factory tolerances would allow a gun to print 3"+ 30 yard groups, especially with the same company's best (and very good) pellet. I have not pulled the barrel to inspect it, that will have to wait till after sunday's FT match. (my boy's rifle) But I'd bet it's loose enough to nearly let a pellet fall through. That, I view as a QA shortfall.
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Joined: November 17th, 2006, 3:51 am

October 12th, 2008, 4:22 am #10

you don't have to buy from a tuner....but you take your chances. My .177 Disco shoots great. Crosman asked no questions and offered to send a new one. I suspect they monitor this forum and/or know about their QA issues.

Along the same lines....not only does this barrel perform poorly, it also does something I've not experienced before. I may be a technique problem on my part, but, it will make multiple groups. That is, out of, say 8 shots, two separate groups will materialize. And the groups will be really tight. If someone knows its the shooters problem, please tell me what it is.
..nearly always a barrel stability issue, it's coming to rest between shots (and the vibrations associated with a shot) at two different places.

Take off the front sight/brake assembly. It's radiused along the bottom to fit against the gas tube at the rear. Lay a short single thickenss of electrical tape along the bottom of that radius where it bears on the gas tube (or along the gas tube where that radius fits) and reattch. Will shoot to a diffeernt point of impact, but if it cures the two-group tendency, just re-sight in.
Last edited by gubb33ps on October 12th, 2008, 4:23 am, edited 1 time in total.
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