While looking at different PCCs I ran across a video at
View: https://www.youtube.com/watch?v=rxcFK3rcqU8&
. They tested Speer Gold Dot and Federal HST with both 124 and 147 grain bullets and in both regular and +p pressure levels. Test guns were conventional pistols with 3.5 and 4.7 inch barrels and PCCs with 12.5 and 16 inch barrels.
The 124 grain Gold Dots showed about 300 more fps going from the shortest to longest barrel and the heavy bullets showed little difference. The Gold Dots started coming apart due to the extra velocity. Like you said, sometimes faster isn't better. It looks like the best choice for PCC defense ammo is the heavy stuff. You lose the extra energy more velocity would give you but gain a bullet designed to perform well at the velocity it will achieve in both a pistol or PCC
Exactly. I have that video embedded in the link I provided in an earlier post along with some others.
That link again (which has the charts and still photos along with several videos)
http://sepboard.us/viewtopic.php?f=19&t=15
The 124+P GD for example going from a 3.5 inch pistol to a 16 inch PCC yields a 281 fps gain in velocity. That is right around a 25% increase in velocity which is substantial. The trick, as we've mention isn't just the velocity increase but having a bullet that can handle that increase and still perform. Using the 124+P GD again, it yields 15 inches of penetration and expansion to .70. I disagree with LG's assessment that it's 'beyond controlled expansion'. The +P held together and while it didn't have the 'classic' flower petal still expanded well to .70. And again, the important factors are the penetration and that it held together. This is what I generally have my Sub2K loaded with since it's my old off-duty round.
Conversely, the standard pressure GD is an example of a round that I would not use. Although it had a gain of 279 fps in this test, it only penetrated to 10 inches. Outstanding expansion put at the expense of penetration.
While there wasn't a huge increase from 12.5 inches of barrel to 16 inches, there was an increase in the 115 and 124 weights. The 147 though, as you mentioned, may very well be a good round in a shorter barreled PCC as you get slight gains but nothing crazy. In a 16 inch barrel you'll likely get comparable performance to a pistol although you'd get the expected increase in sight radius and controllability of the platform
So care needs to be taken with ammo selection.