I thought I read that the 120 grain 300 blackout was supposed to have equal or better ballistics trajectory due to the higher ballistics coefficient even though it is heavier.

Went to the range and the 120 grain Barnes is 5 MOA or 10 clicks up to be on point with the 110 grain on my TA31 ACOG.  Big difference!

16" LWRC DI 300 Upper

What distance was each round zeroed at? What distance did you shoot with both to check the trajectory?

I zeroed the 110 gr at 100 yards then loaded the 120 gr and tested at 100 yards.

10 clicks got me back to zero for the 120gr.  Clicked back 10, loaded a 110 and was back to zero.

With same 100 yard zero, going to test out 200 yards this weekend using my BDC

Are any 300blk rounds all that close to a TA31 BDC? I’m normally the one saying ‘they’re close enough’ most of the time, but I have to think they’d be a good bit different in this case. I’d think the 7.62x39 or 6.8 ACOGs would be closer.

I thought about trying the 120 but decided to stay with the 110 for the velocity. Want that bullet to peel back as much as possible on its target.

The 120gr having a lower poi zero at 100yds didn't mean it won't drop less at 2-300yds vs the 110gr.

That doesn't tell you anything about the ballistics of a round, different rounds will have different points of impact. You need to zero one at 100, then take it out farther and get data, then do the same for the other load.

Keeping 100 yard zero w/ 110 grain, I'll give feedback on 50 yard and 200 yard adjustments required (which gives POI delta at 3 points).  That should give indicative trajectory?

Are there any ballistics calculator out there that i can modify / offset with field data?  I have Strelock and it suggest that I have similar POI which is not what I am experiencing.  Played around with different G1/G7 models.

My scope is a TA31M4RCOM150.  2 clicks = 1 MOA = 1 Inch @ 100 yards per Trijicon.

Strelok has no clue how your barrel shoots.  Different bullets/loads can have different POI, in some cases quite significant.  For example, I have a .280 that I use as my go to deer gun.  My go to load is 140gr Nosler Accubonds over 57gr of RL19.  I tried out some 139gr GMX's over the same powder charge.  At 100 yards, the GMX's impacted like 6" higher than the NAB.  Once I re-zeroed, I found their trajectories to be very similar.

The adjustments you made when trying the different load was simply an impact adjustment, it has nothing to do with trajectory.  Once you start shooting with both at distance, I think you'll find that their trajectories are similar, even though their point of impact's are different.

You've been had by clever marketing people. All this contemporary bullshit about how ballistic coefficient will set you free is exactly that. My favorite is the 224Valkyrie, "Finally a round that stays supersonic past 1300 yards!" Oh, thank the Lord, that's exactly what I've been needing!

Kidding aside, the post above this one is correct. 300BO is extremely sensitive to bullet weight given the small case capacity. The 110gr barnes is going to give about 2270fps from a 12.5" barrel. The 150gr FMJs are going about 1,800 fps, if you're lucky. A 120-125 will do about 2050, maybe 2100. That's definitely going to have a different POI.

A higher BC might mean a similar POI at a given distance but you need to figure out where that cross over is and it's most likely going to be quite a ways out.

-Stooxie

Still need to get to a range, but at least this thread will capture 3 POI (50, 100, and 200) with the 2 grains.  At this time, seems I am sticking with 110 grain Barnes for when I am actually using the blackout for some close distance hunting.

On another note, the Hornaday Full Boar VMAX 110 gr has same POI as Barnes 110 @ 50 and 100 yards.  I can just switch between the bullets with a zero on my ACOG.