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All Springer/NP/PCP Air Gun Discussion General => Air Gun Gate => Topic started by: 4932msmith on February 14, 2012, 02:16:19 AM

Title: choppin barrels?
Post by: 4932msmith on February 14, 2012, 02:16:19 AM
Several months ago I did not know about this or similar sites, but I did know that it was almost impossible to get my beeman Ram 22(RS2) out the window of my truck while on pest patrol. So out comes the hacksaw and she went from 47.24" to just over 42". I never gave accuracy or performance a second thought, and went strictly for ergonomics. Luckily[/b] it still shoots as good as it ever did and without a chrony I cant tell the difference in power. Is there any kind of formula or rule of thumb for best results when shortening the barrel?
Title: Re: choppin barrels?
Post by: Kailua on February 14, 2012, 04:01:49 AM
I would say about 10'' would be the shortest I would go.  Depends of the grooves and at what length it would give a full twist on the pellet rotation.   I have to say I am no expert on this.  Really just a basic knowledge am sure someone will help us out with more precise info.
Title: Re: choppin barrels?
Post by: Mark 611 on February 14, 2012, 07:47:59 AM
I agree with Kailua on the length I would not go any shorter than 10''  :P
Title: Re: choppin barrels?
Post by: Onebaddj on February 14, 2012, 05:36:41 PM
As a geneneral rule you will lose about 10 fps per inch.and the shoter the barrel the higher the pressure will be when the pellet exits the barrel making it louder.
Title: Re: choppin barrels?
Post by: 4932msmith on February 14, 2012, 05:42:10 PM
The RS2 in question went from 18.5 to 15.25 breech to muzzle, additional length was all muzzle brake. The other thing which I forgot to mention is that it is much more difficult to cock now due to decreased leverage, at some point that would have to be considered.
Title: Re: choppin barrels?
Post by: Kailua on February 14, 2012, 07:01:10 PM
May carry a plastic pipe to assist in cocking if the front sights are taken off.
You might look into a B21 copy of the RWS 48.  Both side lever cocking.
Title: Re: choppin barrels?
Post by: robert w on February 14, 2012, 08:33:07 PM
id take a brass screw and chuck it in a drill put sone ver fine valve grinding compound and use it in the end ot the barrel making a crown accuracy suffers from cut barrels sometimes just apply light pressure and let the compound work after a few seconds stick a q-tip in the crown and turn it see if any cotton sticks to the barrel if some does use the screw  some more and when satasfied clean the bore and see how nice it shoots
Title: Re: choppin barrels?
Post by: 4932msmith on February 14, 2012, 11:21:20 PM
I did a recessed crown using 3/8 drill bit-chamfer bit-220,320,400 sandpaper and finished with dremel mounted buffing wheel. The accuracy remained the same before and after.
Title: Re: choppin barrels?
Post by: 4932msmith on February 14, 2012, 11:25:03 PM
I've not had much luck with the brass screw, but have never seen it done so I'm probably doing it wrong.
Title: Re: choppin barrels?
Post by: robert w on February 14, 2012, 11:27:17 PM
well if you did that ok but qtips are a great way to see if there are any burrs you must have got lucky with your first cut but as long as you get your swing in when you need to shoot. you might be makin a mini carbine lol
Title: Re: choppin barrels?
Post by: robert w on February 14, 2012, 11:30:21 PM
most use a round headed screw but if it shhots straight its ok if it acts up try that i recrowned a couple of barrels and others have here also  i just dont want you unhappy with it later
Title: Re: choppin barrels?
Post by: makenzie71 on February 14, 2012, 11:34:05 PM
Well if it shooting accurate now then there's nothing to fix.  Not worth over-working if you can't find a problem.

Unfortunately you're not going to be able to correct the loss in leverage without adding leverage...which defeats the purpose of you having cut her down.  The bright side of this is that it will encourage you to hit your mark the first time :)