Choosing the right caliber

[1377x]

i saw a rhread the other day downing .20 cal
it was said it robs power something or another
if i find the link i'll post it

[cmj21973]

Good info and food for thought.
http://www.pyramydair.com/article/Airgun_Calibers_June_2003/4

[Plekto]

The article appears to mostly be a reprint of an old article from Beeman as near as I can tell, with some changes here and there.

Times have changed recently.  Almost all PCPs are now .22.  Almost all Field Target competitions are now .22 as well. (power is still regulated close to older levels, as expected, to be fair to .177s)  Accuracy is identical for a .177 and a .22 match grade gun as you'd expect.  So it's really a PCP/non-PCP divide that's happening currently, with non-PCPs being mostly .177 and PCPs being mostly .22 and larger.   CO2 is a mixed bag. 

Larger calibers are sometimes more efficient in utilizing the power that is available.  This is due to the fact that the gas has more time to push against the pellet if it's going slower.   With a spring-piston gun, this is essentially nil as the mass of the piston and air chamber is almost always identical - just the barrel is changed.  With HPA, it's somewhat pronounced as a lot of the gas simply is wasted on each shot (1 or 2 ft-lb at most, IME).  With CO2, it's quite large as it's an expanding gas, not unlike a real firearm.  A .177 CO2 gun and a 9mm CO2 gun of the same design can have a 20% difference in energy at the muzzle.  As expected, CO2 also shows the largest change in velocity for a longer barrel.

So it's not just what caliber.  It also is that kind of power plant you're using. 

[Colt25]

So it's not just what caliber.  It also is that kind of power plant you're using.

Yes.

[mudduck48]

Correct me if I'm wrong, but if the .20 is better, everyone on this forum could write and call Crosman to just make a barrel to fit our guns. This would be a done deal, maybe. Just a thought.

[Cowray]

If your going to shoot in 10 meter competition you will want .177. It's all that it's allowed on the rules. Of course probably wouldn't be shooting a Crosman in 10 meter competition.

[AZAG]

So...no one has spoken up for .25 yet? 

[jdub]

Through a great deal of testing .20 caliber has been shown to have a higher coolness coefficient than the other calibers.



Any true Sheridan fan will back me up on this one.   And now that I have a .20 cal Beeman R7 to go along with my two Sheridans I'm even more convinced. 

And finally .20" = exactly 5mm.  Not 4.5mm.  Not 5.5mm.  Just a perfectly straightforward, decimal-point-free, 5mm. 

[cmj21973]

Through a great deal of testing .20 caliber has been shown to have a higher coolness coefficient than the other calibers.



Any true Sheridan fan will back me up on this one.   And now that I have a .20 cal Beeman R7 to go along with my two Sheridans I'm even more convinced. 

And finally .20" = exactly 5mm.  Not 4.5mm.  Not 5.5mm.  Just a perfectly straightforward, decimal-point-free, 5mm. 

Hate to burst you bubble, but 5mm = .19685  .20cal=5.08mm

Who's kidding who, I shot your bubble with a .22cal 5.588mm pellet!

[jdub]

Hate to burst you bubble, but 5mm = .19685

Who's kidding who, I shot your bubble with a .22cal 5.588mm pellet!

Seriously??  5 decimal places??   Us .20 cal owners would rather spend our time shooting our very cool .20 cal/5mm air guns than trying to memorize the value of Pi to 5 decimal places

.22 is like a Ford F350 dually.  .177 is a hot little Suzuki Hayabusa.  .20 caliber like an Aston Martin DB9.   

You can't shoot my bubble because your dually can't catch it.   The Suzuki will just bounce off the bubble and leave you with nothing but bad helmet hair.   The Aston, like the .20, not only gets you there but does it with style.   

This is all very scientific of course.   

[cmj21973]

Seriously??  5 decimal places??   Us .20 cal owners would rather spend our time shooting our very cool .20 cal/5mm air guns than trying to memorize the value of Pi to 5 decimal places

.22 is like a Ford F350 dually.  .177 is a hot little Suzuki Hayabusa.  .20 caliber like an Aston Martin DB9.   

You can't shoot my bubble because your dually can't catch it.   The Suzuki will just bounce off the bubble and leave you with nothing but bad helmet hair.   The Aston, like the .20, not only gets you there but does it with style.   

This is all very scientific of course.   

If I ever run out of .22cal pellets, I go to Walmart. it's 10 mile round trip; open 24/7; closed only on a couple of holidays. Resupplied and back shooting in 30 minutes or less.

How about you?

[jdub]

If I ever run out of .22cal pellets, I go to Walmart. it's 10 mile round trip; open 24/7; closed only on a couple of holidays. Resupplied and back shooting in 30 minutes or less.

How about you?

Ouch!   I uh... sit on the porch waiting for the FedEx guy?

Well played.   

[mr007s]

.177 pellets will shoot from a .20 barrel. Heck, I mistakenly shoot .177 in my .22 all the time

[pirouge]

   .177 for feathers, .22 for fur

[Colt25]

If your going to shoot in 10 meter competition you will want .177. It's all that it's allowed on the rules. Of course probably wouldn't be shooting a Crosman in 10 meter competition.

I shoot a 10m crosman target rifle.
crosman challenger 2009s.