Air Venturi PCP setup for iguana problem

[Treks]

The lower the FPS the faster the pellet drops. The more hold over, the harder the shots. Yes, you can holdover but why not have a flat tragectory to start? Why make it harder than it needs to be? FWIW, this isn't competition, 925fps is accurate enough. If it's a head shot, how much FPE is needed for a pass through at your distance? Why use more fpe than needed? Why not have flat? Don't get caught up in larger bore is better. It gives you more fpe but these are iguana's not coyotes.

All JSB using Hardairmagazines's BC
.177 8.4g 925 fps at 25 yards 11.54 fpe, 1.42" drop at 25 yards
.177 13.4g 925fps at 25 yards 23.1 fpe, 1.31" drop at 25 yards
.22 18g 880 fps at 25 yards 25.9 fpe, 1.49" drop at 25 yards
.25 25g 600 fps at 25 yards 16.96 fpe 3.19" drop at 25 yards

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He already bought a .25 air rifle and scope clicks negate drop concerns. OP also mentioned a coyote problem which typically would lend itself to a larger caliber, as you have pointed out.

 

[Tony D’Agostino]

I have a GAMO Swarm Magnum pro 3i. It’s in .22 Cal. Works fine with Iguana’s. Using Hornet H&N pellets, generates about 930 FPS And about 28 Ft LBs. More that enough power to take down Iguana’s although the larger ones do require a neck or head shot to fall asleep. Otherwise a follow-up shot works fine. The Hornets are a 16 grain pellet. I may experiment with some 18 - 20 grains pellets for more stopping power on the big boys. But really not a big priority. Note: the Magnum requires about 50lbs of cocking pressure. So only recommended for the fit. Thought of switching to PCP, but love the fact that getting air isn’t an issue With the GAMO. Down the road, I may get an entry level PCP like the Gaunlet or Avenger, to play around with, and keep the Magnum as a solid backup, because it’s a really nice pump action rifle.

 

[Tony D’Agostino]

I’m not an expert, but I think that with the power of the Magnum and a heavier 22 Cal, Pellet, 20 grain, or so, you can even experiment with slugs, which I understand the Magnum handles well, you can still generate approx. 800 plus FTS, That’s getting somewhat close to the power of a 25 Cal, without having to worry about flyers hitting the neighbors.