Hey Timmy.. I've got some too.

[RCnMo]

I figured I'd try to choke the barrel (or the 10" left of it) on my Quest. I will say to all the naysayers out there that there was an improvement on the groups and I now feel resistance in the last inch of my barrel when pushing a pellet through. I made these after seeing Timmy's NASA blocks and figured what the heck. I used a 12ton press and turned the barrel 90 degrees between squeezes. I was skeptical because I couldn't 'crush' the barrel and figured I wasn't doing anything. Well, when I finished up, the pellet definitely had more resistance at the muzzle than before. The groups shrank too!

[gamo2hammerli]

That`s way cool.  I think I need to do that on my Sierra Pro.  Your group shrunk dramatically.....  good job!!!!

[spark22]

you need to make those for sale I need one for my quest

[gunsup0331]

hmmm.  how much to send you a barrel and have you squish it for me? (Not incl. postage obviously)

[RCnMo]

Hey Brandon, I sent you a PM

[WesCombs]

What were the before and after velocities?

[RCnMo]

It was shooting 950 with cphp's and that was with the chopped barrel. I tamed it down a bit the other night by machining down the first 'step' on the guide and it is shooting 850-860 now. It's a much more tame rifle now. I also tried some superdomes this evening and they are grouping pretty decent. I plan on trying them out tomorrow at 30 yards to see how they group.

yery nice Ralph,
good looking groups and nice blocks.

[RCnMo]

Thanks Craig

[melloroadman]

IMO chocked barrels generally work best . I measured the inside of my 3 crosman barrels at the bore not the grove depth and all 3 were .177 . I measured both of my rws barrels and they were .174 . If you go to our library you will see a pellet chart my Straight shooters that give the sizes of many pellets . So far all my rifles have liked the cph but none have liked the cpl . I can see why now . I measured my lights and the heads were .174 . Were as the heavies the head is .178 . With the lights the heavy head of the pellet is never touching the barrel let alone getting into the rifling . All the weight is traveling on the skirt and the pellet is trying to wobble as soon as it leaves the barrel . . Also the length of the cph I believe is helping it to fly true as well . Marvin

[RCnMo]

Good info Marvin. I've found that the Superdomes seem to group tighter than the cpl's in this thing too. It's still far from a tackdriver. It probably needs a barrel. I can't think of anything else to do to it.

[Gene_SC]

When I read about true choked barrels the manufacturers generally build the choke into the barrel with a gradual choke narrowing down to an approximate .005 over a certain determined distance. I have also read that choking a barrel post manufactured barrel works as well. But what I do not understand is how would you know the tonnage to apply with a barrel clamp as you have made? Also you have to remember that an air rifle barrel's do not have the hardness as a powder burner barrel's.

Just my thoughts..

Gene

try a little heavier pellet.
milbro clipper 9.0 grain
beeman kodiak match 10.6
this made all the differance for me.

[melloroadman]

IMO that pellet chart in the library is a money saving , stress reducing chart . Marvin

[RCnMo]

Gene, it was a shot in the dark. This rifle never has shot well for me and I figured I would give it a squeeze because it couldn't hurt. Like I said in the beginning, it didn't appear to be doing anything when I was squeezing it in my press, but when I ran pellets through the bore I could definitely feel resistance at the muzzle. I shot it afterwards with the same pellets and same distance with better results. I know this whole choke thing was a drawn out ordeal on an earlier thread and I was a skeptic, like many. Somehow, some way, I have a choke at the muzzle of this barrel now.