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Suggestions for optic for 300 BLK w suppressor

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October 05, 2021, 11:02 AM
Jimbo Jones
Suggestions for optic for 300 BLK w suppressor
Hi all

Putting together a suppressed 300 BLK rifle (my first in this caliber) and thinking about optics and looking for people with experience with this round

Full-length barrel, optics only likely, not thinking MBUS,

Was thinking max range for optic would be out to 200 yds given that the drops are >> 12" even for supersonic ammo past this point.

Maybe something in the 1-6x or 1-8x range, or possibly a fixed power like a Sig Bravo 5 or an ACOG

Just looking for people to share their experiences and opinions...

Thanks!

JB


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October 05, 2021, 11:16 AM
KSGM
Given that drop is a factor, something with a BDC is probably advisable. That rules out a dot with a magnifier, unless you go Eotech. If you're considering an ACOG, maybe throw in a bit more and get a Specter.
October 05, 2021, 01:27 PM
fritz
quote:
Originally posted by Jimbo Jones:
Putting together a suppressed 300 BLK rifle...
Full-length barrel, optics only likely
Was thinking max range for optic would be out to 200 yds given that the drops are >> 12" even for supersonic ammo past this point.

Maybe something in the 1-6x or 1-8x range, or possibly a fixed power like a Sig Bravo 5 or an ACOG

When you state "full-length barrel", I assume a 16" AR-15. The following are the JBM ballistics for a few loads, based on estimates from my 11" 300blk. Assuming 3,000' density altitude, 2.5" scope height over bore, 100 yard zero.

110 Vmax, MV of 2500 fps
1.3" drop at 150 yards
4.5" drop at 200 yards
10.0" drop at 250 yards
18.0" drop at 300 yards

125 HPBT, MV of 2200 fps
2.0" drop at 150 yards
6.4" drop at 200 yards
13.5" drop at 250 yards
23.8" drop at 300 yards

150 FMJ, MV of 2000 fps
2.5" drop at 150 yards
8.0" drop at 200 yards
16.5" drop at 250 yards
28.6" drop at 300 yards

The drops are definitely less than 12" at 200 yards. With the right load, I experience good accuracy to 300 yards, even 400 yards with my SBR blackout.

Should you use a 50 yard zero, the drops are less at each of the distances, but the POI will be slightly above your POA at 100 yards.

There is no magic "one optic does everything" for the various 300blk loads. Loads can vary dramatically in bullet weights, bullet types, muzzle velocities, and flight ballistics. As a result, BDC reticles may work, or they may not.

I suggest a LPVO. You should carefully consider your use, targets, distances, and ammo before buying an optic.
October 05, 2021, 01:49 PM
Rustpot
Fritz - take a look at the subsonic numbers for drop. They fall pretty fast.


I haven't looked at my 300 build in a while, but it's a little 8.5" pistol setup. I had settled on getting one of these if I end up back behind that gun. Basically a poor man's ACOG without the fiber/tritium. 2x might be a bit short on magnification for your preference.

https://www.primaryarms.com/pr...b-m5-7-62x39-reticle

EOTech does make a 300BO reticle with 1-2 BDC dots, a little more crude. Their G33 3x magnifier was the standard for years, the new released generation magnifiers are supposed to be better and smaller.

LPVO is the "easy button" answer for needing close-to-intermediate range optics. Hard not to suggest one of the many good scopes out there.
October 05, 2021, 02:29 PM
fritz
quote:
Originally posted by Rustpot:
Fritz - take a look at the subsonic numbers for drop. They fall pretty fast.

Yes, I'm well aware of the large drops for subsonic ammo.
But the OP mentioned supersonic ammo.
October 05, 2021, 03:18 PM
WARPIG602
I use an Eotech on my 10.5. The model with the 2 dots. The dots are almost perfect for switching between subs and supers.

On my Ruger American Ranch, I use a Sig 2-7 BDX. coupled with a Sig RF unit, its a perfect match for 300blk, especially if you find yourself switching back and forth between subs and supers as you can quickly adjust the ballistic profile. Then you just laser range your target and the scope makes all the adjustments moving the red ot where it needs to be for dead on holds.

If you want to forego the range finder part, you can also setup the scope with predetermined distance/subtensions based on your load for hold overs. While I thought it was gimmicky at first Ive come to appreciate it in certain circumstances.


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