What is a good air gun caliber for hunting iguana’s?

[Gameflyer450]

I have a springer air rifle for hunting small game such as squirrels, and I wanted see If it likes heavy pellets for hunting. So I did an accuracy test with some JSB 25 gr pellets in my rifle and they dropped around a 1 inch at 18 yards. So should I stick in the 14-17 grain pellet range? 

 

[Wv7o]

Gameflyer450 with the 14 -17 grain pellets what is the drop at the same distance and how is the grouping?

 

[Curt]

I wish I had these guys around to hunt. Seems like it would be a ton of fun. 

 

[Gameflyer450]

Wv70, sometimes my pellets hit way below with the heavier ones. Then my lighter pellets (14-15 grains) generally have better groups. That could also be me shaking because I know it can handle the 15.4 grain Gamo Red Fire .22 pellets cuz they generally have way tighter groups. Like half and inch or tighter. 

 

[Gameflyer450]

Out of any break barrel rifle’s such as the Gamos, I would not recommend 25.39 grain JSB Monsters. Why? Because they always seem to drop an inch or more every time I shoot them back at 18-20 yards. 

 

[Sanguily]

I have been hunting Iguanas in south FL for 2 years now and I completely agree that accurately placed head shots just behind the eye is essential for a clean kill. Anything into the body is merely an annoyance to these animals, especially the larger ones. I started out using a 22 Benjamin Marauder with 16 grain Predator Polymags going about 850fps. Great pellets. Lethal on squirrels out to 40 yards on either a vitals or head shot. On the Iguanas it was a different story. One shot kills on anything longer than 2' was challenging. I have since stepped up my game. I am now running a Umarex Gauntlet G2 in 25 cal. I am pushing JSB King Heavy MKII 33.95gr pellets at just under 900fps. Head shots on any size Iguanas is almost immediately lethal. The difference in moving up to to the 25 call delivering over 50 FPE is amazing. IMO, Don't waste your time with 177 or 22 on Iguanas., go with 25 or even 30 if you are hunting in an area where you can use that much power.