Hello all i just received my first springer the RWS 350 (its actually my first rifle/gun of any kind). Its a great rifle to shoot but a tad too long in the barrel and i am interested in getting it shortened. I wanted to know what the advantages and disadvantages of shortening a barrel are. What would be the ideal length to shorten the 350s 19.25in. barrel? Also what exactly is crowning and choking? I apologize for what I'm sure are simple questions for you guys and I also appreciate your time and responses, thank you.

-Damian-

Hey new guy!


Im not as up to speed as some of these guys on here but Ill give it a shot.


My understanding of chopping the barrel is that with all firearms and spring guns and especially the the 350,is that there is a vibration which makes a whipping motion which throws off the accuarcy somewhat.

By chopping the barrel, the barrel in effect, becomes stiffer with less vibration to throw of the pellet.

The crowning is the inside lip of the barrel at the end of the barrel, what happens is,sometimes the crowning is off from the factory , then the pellet does not leave the barrel evenly like its supposed to. Letting air escape unevenly from one side of the pellet before the pellet leaves the barrel, pushing the pellet to one side . re- crowning the barrel will fix that.

Im still unsure if the Dianas are choked or not, I belive they are not, but I could be wrong here. Chokeing is the narrowing of the inside of the barrel at the end of the barrel.The end of the barrel is sleightly narrower than the pellet itself forceing it through a smaller hole .


You really dont want to try these at home ,unless you have some experience with it. But the best thing you can do is to send it to a good tuner.

John in PA is highly recomended , he did the tune on my 350 mag which was just unshootable, and turned it into one sweet shooting rifle. Its worth the money and you wont regret haveing it done. He comes AAA rated on this forum and I never read one complaint about his work.

The trick to accurizeing your rifle is reduceing vibration throughout the gun .

If your useing a scope , get the best mounts you can buy, your going to need good scope mounts on a 350 , theyre notorious for scope shift. I have the BKL 247 D mounts from straight shooters . they are expensive but work great.

Someguys use some mounts that dont cost as much but say they are just as good. Ask around.

This is a great place to learn about your rifle. the guys on here are very knowlageable and friendly.

Hope this kinda pointed ya in the right direction.

Awesome, thank you very much for your time and response all the information was very very helpful. I was always under the impression that a longer barrel would produce a more accurate shot but i now know better. Generally speaking what is the length the barrel is usually shortened by?
I was able to find out all the information on John in Pa. He seems like the man to go to and I'm looking forward to shooting him a message soon. Thank you again for all that information its greatly appreciated.

and add one disadvantage,
that when the barrel is shortened and the spring is not replaced with a weaker one, cocking the gun becomes a bit stiffer.
To get a rough idea of how much stiffer,
if you are going to remove say 4 inches of barrel, put your hand in the area where the end of the barrel would be when cut and try cocking the gun from that spot to see if its too much effort or not.
Depending on your build and strength, you decide how short it can be but I would not take it much below 14 inches from breech to muzzle, mostly for practical reasons in a gun like the 350.

I'm sure others will chime in with their views.
good luck.
David

Another disadvantage to chopping a barrel is, You're never going back to open sites again.
Not a big deal if you always scope your rifles but something to think about. I've chopped and choked three 350mags so far and I can say that it changes the firing cycle for the better. I've owned three or four 350mags of my own and I never got use to the tork when fired. The last one I owned I chopped to 16 inches and I really liked the firing cycle after that. It was more of a straight back push and not as much side twist going on.

Crowning a barrel is making sure that all the rifleing grooves end at the same point. If one or two of the groves was still touching the skirt of the pellet as it exited the barrel it would push the pellet of balance.

Choking a barrel is just a matter of making the barrel rifleing slightly tighter right before the pellet exits the barrel. This trues up the pellet before it starts its journey. Welcome to the Diana Forum, John

YEP;

and another OK to this post

like John say's you will loose your open sights immediately when you chop the barrel from 19.3" to 19. 18. 17.or 16" and you will need a SCOPE

RWS barrels are NOT Crowned from the factory

Listen to a SECRET ;Crowning a barrel is making sure that all the rifleing grooves end at the same point. If one or two of the groves was still touching the skirt of the pellet as it exited the barrel it would push the pellet of balance.;

read another secret by a reputable tuner;
Choking a barrel is just a matter of making the barrel rifleing slightly tighter right before the pellet exits the barrel. This trues up the pellet before it starts its journey.;

questions???


warren

PS: John in PA can answers them

and remember "it's 30% the gun and 70% the shooter"

WoW that's alot of great info guys. I would still love to put a couple thousands rounds through the rifle before winter and then definitely send it out for a tune and trigger work. I think this will give me enough time to decide if i would also get the barrel shortened.


PS - John, how is your schedule during winter months. If not too hectic I would love to contact you about having some work done.

PPS - I love getting things modified, my cars, my bikes heck i even modify my watches so i guess my other question is, can the 350 be modified for better accuracy and velocity or is it pretty much one or the other? Thx again guys.

-Damian-

Are all the Diana/RWS barrels choked from the factory?

NO they are NOT choked at the factory they crimp the front of the barrel to install the front sight and that gives them a semi-choke not a full choke

look and see 2 rails in the front of the barrel where the front sight clamps itself

warren

and remember "it's 30% the gun and 70% the shooter"

How are most airgunners crowning barrels? This was being pushed in a powder burner mag a number of years ago. the recommended procedure was using a mandrel, drill and lapping compound. I could never figure out how this ensured that the rifling terminated at 90 degrees to the bore.....It might possibly have de-burred the end of the bore, but I wonder at how the crown to axis of the bore relationship is maintained.

Model48

Here is an answer found by my favorite method, "Google"
-----------------------------------------------------------
"Crowning a rifle barrel, in simplest terms, is shaping the muzzle so
the rifling's edge is protected from impact. Most factory barrels have
a round, convex-shaped crown from bore's edge to the barrel's outside
diameter. That's easy to make and finish, plus looking rather pleasing.

The accuracy part of the crown means the land and groove part of the
barrel must let the bullet's base exit evenly all the way around. When
this happens, gas escapes uniformly and evenly around the bullet's base.
If gas escapes unevenly (poor crown, even unsquare bullet bases), the
point of greatest gas release will push the bullet in the opposite
direction and tilt it. Tilted bullets leaving the barrel just don't
shoot straight; how far they move sideways depends on their velocity,
spin rate, and degree of tilt (or yaw, as it's sometimes called).

Some factory barrels have different-shaped crowns. Some will have the
muzzle faced flat at right angles to the bore from outside diameter to
inside bore diameter. Others will have a flat face, but the lands
will be angled back some amount. A counter-bored crown is set back
from the front-most part of the muzzle, then the inside part will be
either flat-faced or angled."
----------------------------------------------

Here are two "ways" to approach this subject:

A very elaborate method requiring a gunsmith's tools and expertise:

(This is for the extreme target type shooter- mainly firearms not air guns)

http://riflestocks.tripod.com/targetcrown.html

And the simple way that you can do yourself, and only with the "brass woodscrew" part: (Midway's Larry Potterfield series)

http://riflestocks.tripod.com/targetcrown.html

Thank you Sir for taking the time to post that. "Old Tim",,, AKA "Chopper"

It,s hard to say about my schedule with tuning. Sometimes I think its slow and then the next day I get three emails about tunes. Don't worry though, I'll always find time for one more. John

John,

Thank you for the response. You'll definitely be hearing from me again :0)

-Damian-

The Larry Potterfield Video:

http://www.youtube.com/watch?v=OorpZlG28fI

Sorry 'bout that!

Ol Timer
FWB 300S//MM B26-2 .22//Diana 34

someone answered;


"Looks like you left the end of the lands exposed. The original muzzle at least had an 11 degree or so cut. It doesnt matter how clean or pretty the crown is. If the ends of the lands are not cut and only polished you could be short changing your trouble. Good work Larry Potterfield"

..

that video was from Jan 2008 and is a cheap, shade tree mechanic method but if you really want to find your real re-crown you better be carefull

warren

PS: do the Q-tip test to find what you achieved with your re-crowm


and remember "it's 30% the gun and 70% the shooter"