Texan with a shorter barrel?

[LEE IN VA.]

The only downside is see on the gun so far is its a bit long.  I wonder how it would perform with a shorter barrel.  Thinking 5" shorter?

[crosman999]

Wouldn't be any quieter either

[oldpro]

12fps per inch approx. loss maybe more maybe slightly less.

[rsterne]

For a maxed out PCP, the FPE is roughly proportional to the barrel length at a set pressure.... Shorten the barrel 20%, lose about 20% FPE, which is about 10% in velocity....

Bob

[BigBoreJack]

The only downside is see on the gun so far is its a bit long.  I wonder how it would perform with a shorter barrel.  Thinking 5" shorter?

__________________________
It is not a "downside" to have a longer barrel on an air rifle.  The old timers who made the historical air rifles hundreds of years ago came to realize, understand, appreciate this fact, which explains why those old rifles had such long barrels.   That is exactly why, too, that early day black powder shooters, to a smaller degree than early day air rifle makers,  made and used black powder rifles with unusually long barrels (compared to our modern smokeless powder rifles).   Modern Powder burning rifles are much more suitable for shorter barrels, so folks today, who  are familiar with powder burning rifles, get to thinking that short barrels are great for air rifles too, but the opposite is still, and always will be, true,---- to gain the most performance from air rifles, especially from big bore air rifles of say .40 to .50 caliber, one needs a barrel around 31 to 36 inches long.   Airforce airguns understood this, and made their .458 rifle right, in my opinion,  so to cut the barrel off shorter, would only decrease the  performance effectiveness, for use as a real big bore hunting air rifle, not hindered by compromise.   If you love short barrels; can't stand long barrels, you need to be shooting firearms; not air rifles.   

[MJP]

Well it's not just the long barrel that makes the power, a good valve helps too. It's just where you draw the line between power and economy, I have made a custom condor style gun that uses only one Af part and that is the tank. I'm getting 385 joules from .357 156grain bullet on only 550mm of barrel. Using around 350psi of air per shot. So it's no an complete airhog.

[rsterne]

Barrel length and pressure are interchangeable.... You can reduce one if you increase the other in proportion without losing FPE.... Once a valve can flow all the air it is possible to cram down a given size barrel, all the way to the end, no more power is to gained, however.... but you can still use more air by trying....

Bob

[MJP]

Yeah, just makes more noise and recoil, seem that the shorter the barrel the narrower the sweet spot where you are making power or just waste air. 10J more and you are using twise the air volume. But backing off from 385 to 370J and just 250psi is used.