have a question about my hog gun set up:
.300 blkout, 10.5" barrel 1:8 twist
Pulsar thermal scope

I bought this during covid and the ammo shortage so the only bullets i could find were Fiocchi 125Gr SST. blue tips. I zeroed the gun at 60yds w/ no issues. Targets at 60 yds were kill shots. Noticed at 70-80 yds i would miss.

Went back to paper and here were my results
Fiocchi 125gr SST
60 yard zero:
- 60 yds = on target
- 80 yds = roughly 6" high and 6" right
- 100 yds = roughly 12" high and 12" right.
* sometimes the miss would be way low but 90% were high and right

80 yard zero
- 80 yds = on target
- 100 yds = roughly 6" high and 6" right
* same results as 60 yd zero

*If i zeroed the gun at XX yards then it would be accurate to that distance only. anything past my zero distance was consistently off
I guessed it was an ammo stabilization issue so i picked up some AE 150Gr

American Eagle 150gr FMJ
60yd zero
- 60 yds = on target
- 80 yds = on target

100yd zero
- 55 yds = on target
- 100 yds = on target
- 150 yds = on target

I assumed the gun just likes 150gr bullets so I shot the AE 150g all summer with great accuracy but lack luster kill ratio. Recently I have stocked up on the Winchester 150gr XP rounds in hops to increase the kill ratio. I havent shot these too much yet but it zeroed fine.

Ideally Id like to shoot some of the faster 110gr rounds by hornady or barnes. The Fiocchi results turned me away from the lighter rounds but this set up should stablize 110-125gr with no issues. Do yall think it was a Fiocchi issue or a bullet weight issue?

All of this was UN-suppressed. Hopefully within the next month ill have my suppressor. Ill continue to shoot the supers to keep my 100+ yd shot opportunities available. i have hornady 190gr sub-x for when i want subsonics

It’s usually one of three things.
Ammo
Barrel
Optic

I would suspect the optic first. Change optics and see what happens. Do the same for ammo.

Make sure everything is good and tight.

i first thought there was an issue with the thermal core so i sent it back for inspection - nothing wrong. It has shot the 150gr perfectly fine before and after inspection. IF it was a scope issue it would do it with all gr bullets. I am currently trying to locating hornady vmax or barnes vor-tx 110gr to try. i think it didnt like the fiocchi.

110gr tactx are the best you can get. I definitely wouldn’t rule those out until you try them. But I bet you have a better chance of finding a unicorn right now.

I am going to bet it’s the ammo being out of spec.

A bullet to consider is Speer TNT 125 gr hp, I've ordered them a couple times from Midway, they come back in stock fairly often https://www.midwayusa.com/product/2149663126

I have a cheap 300 blk upper but have had great luck in accuracy using this over Hogdon Lil Gun, sorry haven't got to test on hogs yet

I doubt an ammo stabilization issue with 125g and a 1/8 twist.  With your results being so consistent it must be that your barrel doesn't like that particular round.  Maybe it's the velocity rather than the bullet???

the velocity thoguht was the main reason why i went to a 150gr. but i know guys with 1:7 twist in the same barrel length shooting Hornady Vmax 110g just fine. Im betting it was the fiocchi round it didnt like. Im stocked up on 150gr winchester right now but once i find some vmax 110gr ill buy it (hopefully for under $2.80 a round). I can always sell it if it doesnt work out

VMax at $2.25/rd
Barnes VOR-TX at $3.25/rd

110gr vmax is a great round but due it’s short overall length it doesn’t always feed reliably in some guns. Lancer mags help but, I would definitely test it before buying a ton. Especially at these prices.

It's strange that with the other load, you would be on target at 50 AND 100 yards.

When I zero at 50, I'm a few inches high at 100. How high is your optic above your barrel? What size groups are you getting with the Fiocchi 125 compared with the 150? If your barrel doesnt like the 125 SST it should give you bad groups rather than defy physics.

Without knowing more, I'd suspect that something is off with your zero. I would zero at 100 and you should be 1-2" low at 50 and a few inches low at 200.

alright, I got my hands on hornady vmax 110g. By far the best grouping ammo ive found so far
.75" groups at 100yds. zero hardly changes from 60-130 yds

With the AE FMJ, winchester XP and Vmax shooting consistently the only thing i can see is that the fiocchi did not stabilize or something with the nature with this gun.

Yep. I suggest anyone using this for shtf to run through a mag of the Vmax rapid fire. I have had issues in multiple hosts with the 300 specific Pmags as well as the Gen2s.
Gen 3s seem to work well though.

What do you mean by issues with 300 specific Pmags but the Gen 3 work well?

The only .300 specific Pmags are Gen 3s.

I meant the 5.56 Gen 3s.

Gotcha. I've had good luck with the 110 Vmax in my .300 Pmags and also my 20 round M3 5.56 mags. Maybe I got lucky.

I only have had issues during rapid fire. I don't believe I've had any issues when shooting at a slower cadence.

I don't know what it is different about the Gen3 5.56 mags from the Gen2 5.56 that alleviate the problems I have had. I can maybe see how there may be an issue with the 300 specific mags with their narrower ridges and where they meet up with the section of the Vmax's ogive.

I think Lancer states on their website to only use their 300blk specific mags with the longer subsonics and to use their 5.56 mags on the lighter supers, so maybe the same holds true with the 300 Pmags.