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All Springer/NP/PCP Air Gun Discussion General => Machine Shop Talk & AG Parts Machining => Engineering- Research & Development => Topic started by: ZipSnipe on January 05, 2013, 07:11:58 PM

Title: rimfire rifle for pellet gun?
Post by: ZipSnipe on January 05, 2013, 07:11:58 PM
Ok I have a old in almost new condition Mossberg .22 barrel. that I haven't been able to sell off.

I measured the business end which comes out to .217 and the receiver end is .227.
Also if I look down the receiver end it is reamed out for about an inch and then the rifling starts.

Is it possible for me to use this in a .22 airgun project I want to start?

Any suggestions?
Title: Re: rimfire rifle for pellet gun?
Post by: Motorhead on January 05, 2013, 07:22:15 PM
You can with the largest pellets along the lines of the Big H&N Barracuda 5.54/5.55 head size pellets.

Don't have the exact numbers handy, but .22RF barrels are @ a few thousandths larger in bore size than .22 AG barrels
Title: Re: rimfire rifle for pellet gun?
Post by: ZipSnipe on January 05, 2013, 08:46:27 PM
Yeah I found a pellet chart that shows several makers of pellets that would work.
Title: Re: rimfire rifle for pellet gun?
Post by: Bryan Heimann on January 05, 2013, 08:50:56 PM
eunjin would probably work.  I think you can work with it.  Would make a great pcp barrel IMHO
Title: Re: rimfire rifle for pellet gun?
Post by: rsterne on January 05, 2013, 09:32:29 PM
.22LR is typically 0.222" groove diam, 0.217" across the lands.... .22 cal Airguns are 0.217" groove, and about 0.214" across the lands (smaller if the barrel is choked).... Korean (EunJin) pellets are typically tight, so may work OK....

Bob
Title: Re: rimfire rifle for pellet gun?
Post by: Paul68 on January 05, 2013, 09:38:10 PM
Keep in mind that the rifling twist rates might be significantly different for PB's than Air guns.
Title: Re: rimfire rifle for pellet gun?
Post by: Cal on January 05, 2013, 09:52:37 PM
Twist rates ?

Three will get you five  that there is one turn in 16 inches for just about any air rifle (except Smooth Twist) and any "standard) .22RF.

A bunch of copy cats!  ;-)

Besides , pells  do not rely in spin  stabilization so it's hard to hurt them.
Title: Re: rimfire rifle for pellet gun?
Post by: Paul68 on January 05, 2013, 10:34:47 PM
Twist rates ?

Three will get you five  that there is one turn in 16 inches for just about any air rifle (except Smooth Twist) and any "standard) .22RF.

A bunch of copy cats!  ;-)

Besides , pells  do not rely in spin  stabilization so it's hard to hurt them.

If they dont rely on spin for stabilizing, why rifled at all eh? Of course spin has an effect, and an important one.

There are a lot of threads on this. Yes, 1-16 is a basic standard, but smaller cals with higher intended velocities can vary enough to make a difference. Depends on what the gun the barrel is coming from was intended for.
Title: Re: rimfire rifle for pellet gun?
Post by: rsterne on January 05, 2013, 10:55:55 PM
.22LR is standardized at 1 in 16" twist.... Many airguns are similar, according to LW, they use 450mm (1 in 17.7").... The one that confuses me is the FZ "smooth twist" which is apparently about 1 in 16" over the roughly 2" section  at the muzzle that is rifled (the balance is smoothbore).... but the pellets get so little "grip" in this section they spin as if the twist rate is only about 1 turn in 70-80" (one report said over 13 FEET).... They have virtually no rifling marks on a fired pellet from the wiping action of skidding though the rifled section.... They MUST be relying primarily on drag stabilization, not spin....

Bob
Title: Re: rimfire rifle for pellet gun?
Post by: Cal on January 05, 2013, 11:12:38 PM
Twist rates ?

Three will get you five  that there is one turn in 16 inches for just about any air rifle (except Smooth Twist) and any "standard) .22RF.

A bunch of copy cats!  ;-)

Besides , pells  do not rely in spin  stabilization so it's hard to hurt them.

If they dont rely on spin for stabilizing, why rifled at all eh? Of course spin has an effect, and an important one.

There are a lot of threads on this. Yes, 1-16 is a basic standard, but smaller cals with higher intended velocities can vary enough to make a difference. Depends on what the gun the barrel is coming from was intended for.

Bob

It's a MOSSBERG barrel in .22....

jeesh!
Title: Re: rimfire rifle for pellet gun?
Post by: Cal on January 05, 2013, 11:19:56 PM
.22LR is standardized at 1 in 16" twist.... Many airguns are similar, according to LW, they use 450mm (1 in 17.7").... The one that confuses me is the FZ "smooth twist" which is apparently about 1 in 16" over the roughly 2" section  at the muzzle that is rifled (the balance is smoothbore).... but the pellets get so little "grip" in this section they spin as if the twist rate is only about 1 turn in 70-80" (one report said over 13 FEET).... They have virtually no rifling marks on a fired pellet from the wiping action of skidding though the rifled section.... They MUST be relying primarily on drag stabilization, not spin....

Bob

Bob

 You are confusing me here.

First you say that pell guns  need rifling,
"If they dont rely on spin for stabilizing, why rifled at all eh? Of course spin has an effect, and an important one"

  then you say they must RELY on drag. "They MUST be relying primarily on drag stabilization, not spin.... "

All in 20 minutes time difference., ;-)

Sometimes I just want to throw all the air guns in the river and get back to the simplicity of powder ;-)

Title: Re: rimfire rifle for pellet gun?
Post by: Cal on January 05, 2013, 11:23:45 PM
eunjin would probably work.  I think you can work with it.  Would make a great pcp barrel IMHO

Eunjins slug in my Evanix AR-6 at .218 with very good looking engraving.

Better slug that Mossberg barrel and find something to fit before you start the conversion smithing.
Title: Re: rimfire rifle for pellet gun?
Post by: Paul68 on January 05, 2013, 11:27:14 PM
The way I understand it, and I most certainly can be wrong, is that rifles expected to have higher muzzle velocities can have a lower twist rate and vice versa. If its a basic 22 cal, then it's probably fine.
Title: Re: rimfire rifle for pellet gun?
Post by: Cal on January 06, 2013, 12:30:15 AM
The way I understand it, and I most certainly can be wrong, is that rifles expected to have higher muzzle velocities can have a lower twist rate and vice versa. If its a basic 22 cal, then it's probably fine.

For "bullets" the caliber and length of the projectile plays a significant role in spin stability requirements.  MV times twist rate must meet the caliber and length stability value.  There are online calculators that will show the numbers.

You are right,  a basic .22 barrel will be fine.

I suggest a high power custom build and shoot 38 grain .22 rf bullets at <1000fps!  ;-)  Perfect match
Title: Re: rimfire rifle for pellet gun?
Post by: rsterne on January 06, 2013, 02:56:21 PM
With all due respect, Cal.... It wasn't me that said....

Quote
If they dont rely on spin for stabilizing, why rifled at all eh? Of course spin has an effect, and an important one.

There are a lot of threads on this. Yes, 1-16 is a basic standard, but smaller cals with higher intended velocities can vary enough to make a difference. Depends on what the gun the barrel is coming from was intended for.

Read back....

Bob
Title: Re: rimfire rifle for pellet gun?
Post by: ZipSnipe on January 06, 2013, 10:22:14 PM
Well I intend to use c02.  The barrel looks as if its .217 all the way through .

As I look inside the receiver end its reamed for about an inch then the rifling starts. My plan is to cut the receiver end and ream it for .220  but if the opinion is that I would be better off getting an airgun barrel then thats what I would do but if I can use this and get decent shooting out of it then I would like to use it.
Title: Re: rimfire rifle for pellet gun?
Post by: Motorhead on January 06, 2013, 11:54:23 PM
Just my opinion ... if Co2 is to be your propellent really doubtful your going to be able is getting sufficient pressure to move the HEAVY big head pellets a .22RF barrel will require.
So, that said far as Co2 go's, get a purpose sized AG barrel and use lighter more appropriate pellets and let your project evolve with greater potential of success.

JMO, nuttin more.   
Title: Re: rimfire rifle for pellet gun?
Post by: rsterne on January 07, 2013, 12:03:37 AM
I would push a pellet though the bore with a wooden dowel or soft cleaning rod.... If it offers some resistance and comes out with the head engraved by the rifling, you will probably have success.... If it nearly falls through, and the skirt shows some rifling but the head none, it is likely too loose to work well....

Bob
Title: Re: rimfire rifle for pellet gun?
Post by: ZipSnipe on January 07, 2013, 01:51:49 PM
Thanx guys for your answers I have decided that for $16 a barrel from a 2250 direct from Crosman will suffice and save myself any headaches.
Title: Re: rimfire rifle for pellet gun?
Post by: Cal on January 07, 2013, 09:24:37 PM
With all due respect, Cal.... It wasn't me that said....

Quote
If they dont rely on spin for stabilizing, why rifled at all eh? Of course spin has an effect, and an important one.

There are a lot of threads on this. Yes, 1-16 is a basic standard, but smaller cals with higher intended velocities can vary enough to make a difference. Depends on what the gun the barrel is coming from was intended for.

Read back....


Bob

Bob

Will you please accept my apologies?


To err is human,  to forgive...divine!

Kind regards

Cal
Title: Re: rimfire rifle for pellet gun?
Post by: rsterne on January 07, 2013, 10:25:54 PM
Done!

Bob
Title: Re: rimfire rifle for pellet gun?
Post by: plinker81366 on March 09, 2013, 08:46:58 AM
hi all..hope this helps..in the philippines we usually use rimfire barrels for our pcp rifles..most of the pellets here brands like super zero,silver streak,meteors,quick silver, have .223/224 head diameter..just right for rimfire barrels..now we tried jsb exacts on the rimfire barrel mine a green mountain barrel for a ruger 10/22..no good its to loose..

here is an example of a rimfire barrel using 20 grain silver streaks resized/ unsorted at 60 yards
(http://i1353.photobucket.com/albums/q674/plinker81366/IMG_1059_zpsf1011583.jpg)
Title: Re: rimfire rifle for pellet gun?
Post by: AmBraCol on March 09, 2013, 09:15:22 AM
hi all..hope this helps..in the philippines we usually use rimfire barrels for our pcp rifles..most of the pellets here brands like super zero,silver streak,meteors,quick silver, have .223/224 head diameter..just right for rimfire barrels..now we tried jsb exacts on the rimfire barrel mine a green mountain barrel for a ruger 10/22..no good its to loose..

here is an example of a rimfire barrel using 20 grain silver streaks resized/ unsorted at 60 yards
(http://i1353.photobucket.com/albums/q674/plinker81366/IMG_1059_zpsf1011583.jpg)


That's pretty interesting for a first post.  Welcome to the forum! 
Title: Re: rimfire rifle for pellet gun?
Post by: plinker81366 on March 09, 2013, 09:36:00 AM
thanks for the welcome sir AmBraCol,.. i hope that post helped,
Title: Re: rimfire rifle for pellet gun?
Post by: ZipSnipe on March 09, 2013, 07:16:41 PM
Kumustah Plinker

  I have since given up the rim fire idea for awhile. However seeing that I have not been able to sell the barrel it might become a future project down the road.
Title: Re: rimfire rifle for pellet gun?
Post by: plinker81366 on March 09, 2013, 10:59:41 PM
Kumustah Plinker

  I have since given up the rim fire idea for awhile. However seeing that I have not been able to sell the barrel it might become a future project down the road.

well am okay..hmm you know my language.. if my H & N barracudas arrive i will be trying them out see if there is some barrel/pellet compatibility..
Title: Re: rimfire rifle for pellet gun?
Post by: stalwart on March 25, 2013, 04:13:44 PM
I'm working on 2 rifles using Marlin Micro Groove barrels. Both barrels slugged out with sharp engraving of the skirt, and well defined (but hard for me to photograph) impressions on the head (CPHP). They offer firm, consistent resistance.

I'm hoping the (legendary) ability of Marlins to be accurate with a wide range of ammo will translate to AGs.

I'm breaking in the first one, and I'm very encouraged by the groups it is starting to give me. I'd be interested to see the slugs the Mossberg produces.

Edit: I just coated some with Sharpie, and tried to get a better pic.

Title: Re: rimfire rifle for pellet gun?
Post by: venxxxxx on May 14, 2013, 01:19:54 AM
I'm interested in getting a rimfire barrel to use with custome cast pellets now. ::)