300Blk At Distance

[repiv]

I was having a conversation with someone today about 300Blk and the conversation went to the distance a 300 Blackout could shoot effectively. The person I was talking to said beyond 300 yards they were useless. I have 5 different 300 Blackouts (building a 6th) and I have them setup for doing different things. Subs, Supers, Thermal setup for night shooting, scoped setup for day, etc. However I dont have one setup for distance. I shoot 6.5 Creedmoor, 308 and even 223 to distance.

So the question is really just a curiosity, Im not saying this is a good idea. Although its possibly not a terrible idea. What if someone built a 300Blk AR15 from the ground up where the primary purpose was to shoot distance with supers. I realize if I say effectively that would be subjective but I dont mean artillery shots. I mean how far can 300Blk shoot and stay supersonic? All adjustment done via dialing the scope (say around 60 MOAish max) not maxing the hold of the reticle and then dialing too. You might even take it hunting so whatever the distance is it still needs enough energy to kill a deer sized animal at this distance.
What Barrel length would be used? Twist rate? What bullet would be used? What powder, brass, primer? What brands of parts for the gun itself if you think that matters? How would you do it?

How far to you think the "optimal" setup could shoot effectively?

I have looked at ballistics and I have a guess but I wanted to post here and see what other think. I might even take one of my 300Blackouts, modify it a bit and give this a try just for the fun of it.

Thanks

 

[Clint H]

This document has some interesting comparisons. Not saying it's the end-all be all, and max effective range for any cartridge is always a debatable can of worms, but... might be a useful starting point for you:

Source: https://ndiastorage.blob.core.usgovcloudapi.net/ndia/2012/armaments/Wednesday13590Silvers.pdf

 

[357Max]

I was having a conversation with someone today about 300Blk and the conversation went to the distance a 300 Blackout could shoot effectively. The person I was talking to said beyond 300 yards they were useless. I have 5 different 300 Blackouts (building a 6th) and I have them setup for doing different things. Subs, Supers, Thermal setup for night shooting, scoped setup for day, etc. However I dont have one setup for distance. I shoot 6.5 Creedmoor, 308 and even 223 to distance.

So the question is really just a curiosity, Im not saying this is a good idea. Although its possibly not a terrible idea. What if someone built a 300Blk AR15 from the ground up where the primary purpose was to shoot distance with supers. I realize if I say effectively that would be subjective but I dont mean artillery shots. I mean how far can 300Blk shoot and stay supersonic? All adjustment done via dialing the scope (say around 60 MOAish max) not maxing the hold of the reticle and then dialing too. You might even take it hunting so whatever the distance is it still needs enough energy to kill a deer sized animal at this distance.
What Barrel length would be used? Twist rate? What bullet would be used? What powder, brass, primer? What brands of parts for the gun itself if you think that matters? How would you do it?

How far to you think the "optimal" setup could shoot effectively?

I have looked at ballistics and I have a guess but I wanted to post here and see what other think. I might even take one of my 300Blackouts, modify it a bit and give this a try just for the fun of it.

Thanks

I'm basing the below assumption on what my 8.5" BO does. 1850fps with 155 eldm loaded 2.210 coal.
I shot the above next to my 350L 11.5" with Barnes 170 TSX @2150 & this 350L hits the 200y plate with a lot more authority.

If I were going to try it (I wouldn't)!

16" Barrel Carbine gas
155 eldm 2.210 oal ish
1st choice SBR So Com
2nd choice Lil Gun

2100fps I think 500y is about max for Supersonic and good hit probability if not much wind.
Also I don't shoot anything in moa but @ 500 per below that's 20.3 moa or 5.9 mil.

 

[Tex68w]

I've never engaged anything beyond 200 yards with my 300BLK, but this was the result of a headshot at 171 yards with Barnes 110's out of my 9" SBR. I'd feel confident taking a deer up to 200 yards if that were the best opportunity presented to me.

 

[wvfarrier]

The furthest I have had my seekins 16" 300blk is 400 yards using the 110 Speer Spire Points over a max charge of Lil Gun. I did not bother dialing in, just set my lvpo dot on the top of the silhouette and it would consistantly hit right at the where the solar plexus would be.

 

[MO Fugga]

I was fucking around with GRT the other night, and velocity continues to increase, even with a 30" barrel. After 14-16, it's minimal gains.

 

[Sterlingb06]

I was having a conversation with someone today about 300Blk and the conversation went to the distance a 300 Blackout could shoot effectively. The person I was talking to said beyond 300 yards they were useless. I have 5 different 300 Blackouts (building a 6th) and I have them setup for doing different things. Subs, Supers, Thermal setup for night shooting, scoped setup for day, etc. However I dont have one setup for distance. I shoot 6.5 Creedmoor, 308 and even 223 to distance.

So the question is really just a curiosity, Im not saying this is a good idea. Although its possibly not a terrible idea. What if someone built a 300Blk AR15 from the ground up where the primary purpose was to shoot distance with supers. I realize if I say effectively that would be subjective but I dont mean artillery shots. I mean how far can 300Blk shoot and stay supersonic? All adjustment done via dialing the scope (say around 60 MOAish max) not maxing the hold of the reticle and then dialing too. You might even take it hunting so whatever the distance is it still needs enough energy to kill a deer sized animal at this distance.
What Barrel length would be used? Twist rate? What bullet would be used? What powder, brass, primer? What brands of parts for the gun itself if you think that matters? How would you do it?

How far to you think the "optimal" setup could shoot effectively?

I have looked at ballistics and I have a guess but I wanted to post here and see what other think. I might even take one of my 300Blackouts, modify it a bit and give this a try just for the fun of it.

Thanks

I'd start with a 20-22" barrel to get a good balance of velocity and portability. A 1:8 or 1:7 twist rate would help stabilize those longer bullets. Speaking of bullets, I'd go with something like the Sierra 220gr MatchKing or Hornady 208gr A-MAX. They've got a high ballistic coefficient and would retain energy well at longer ranges.

For powder, I'd choose something like H4350 or RL17. They're slow-burning and would help maximize velocity while keeping pressure in check. Lapua or Norma brass would be my choice for consistency and accuracy. And for primers, I'd go with Federal 205M or CCI 450 - they're reliable and get the job done.

As for the gun itself, I'd opt for high-quality components from brands like Bartlein, Aero Precision, Geissele, and Nightforce.

 

[Hecouldgoalltheway]

I'd start with a 20-22" barrel to get a good balance of velocity and portability. A 1:8 or 1:7 twist rate would help stabilize those longer bullets. Speaking of bullets, I'd go with something like the Sierra 220gr MatchKing or Hornady 208gr A-MAX. They've got a high ballistic coefficient and would retain energy well at longer ranges.

For powder, I'd choose something like H4350 or RL17. They're slow-burning and would help maximize velocity while keeping pressure in check. Lapua or Norma brass would be my choice for consistency and accuracy. And for primers, I'd go with Federal 205M or CCI 450 - they're reliable and get the job done.

As for the gun itself, I'd opt for high-quality components from brands like Bartlein, Aero Precision, Geissele, and Nightforce.

Just no.

So much no..

 

[repiv]

Yeah I would agree with a no to those heavier, 208gr and 220gr bullets for 300blk unless someone has done it then I would love to hear more. Although those are great for subsonic. Im not sure how the dead pig pictures at 200 yards helps, but thanks for posting and good shooting. On our land the setup is such that I mostly get a shot at deer and pigs between 200 and 250 yards. Its just laid out that way. But when you are used to shooting out to 1000 yards (not with 300blk) 250 yards is not a difficult shot.

Most of what I have been reading the bullet makers dont make many "serious" long range bullets under 155gr for 30 Cal. (why would they) There are some bullets at 125gr but they are not really for long range in 30 cal. The the ballistics and load data I read seemed to peak in the 175gr, 178gr, and 180gr bullets. I think the 178gr was probably best option from what I saw. Again I didnt look at it too long and I certainly have not tried this yet. Maybe somebody else has a better option and actual experience.
Most of the charts, and calculations I looked at, even with the better powders, the bullet is going to have a difficult time making it to 700 yards without falling transonic.
I have not tried any of this yet so its all just theory right now unless someone has shot out to 700 or beyond and stayed supersonic, then please tell us the secret sauce of how you did it. .

I think I will try this for the fun of it though.

Thank you all for the replies.

 

[Haney]

I'd start with a 20-22" barrel to get a good balance of velocity and portability. A 1:8 or 1:7 twist rate would help stabilize those longer bullets. Speaking of bullets, I'd go with something like the Sierra 220gr MatchKing or Hornady 208gr A-MAX. They've got a high ballistic coefficient and would retain energy well at longer ranges.

For powder, I'd choose something like H4350 or RL17. They're slow-burning and would help maximize velocity while keeping pressure in check. Lapua or Norma brass would be my choice for consistency and accuracy. And for primers, I'd go with Federal 205M or CCI 450 - they're reliable and get the job done.

As for the gun itself, I'd opt for high-quality components from brands like Bartlein, Aero Precision, Geissele, and Nightforce.

Pleasae delete, you are thinking of a different round ...or have no clue what you are talking about .

 

[Hecouldgoalltheway]

Yeah I would agree with a no to those heavier, 208gr and 220gr bullets for 300blk unless someone has done it then I would love to hear more. Although those are great for subsonic. Im not sure how the dead pig pictures at 200 yards helps, but thanks for posting and good shooting. On our land the setup is such that I mostly get a shot at deer and pigs between 200 and 250 yards. Its just laid out that way. But when you are used to shooting out to 1000 yards (not with 300blk) 250 yards is not a difficult shot.

Most of what I have been reading the bullet makers dont make many "serious" long range bullets under 155gr for 30 Cal. (why would they) There are some bullets at 125gr but they are not really for long range in 30 cal. The the ballistics and load data I read seemed to peak in the 175gr, 178gr, and 180gr bullets. I think the 178gr was probably best option from what I saw. Again I didnt look at it too long and I certainly have not tried this yet. Maybe somebody else has a better option and actual experience.
Most of the charts, and calculations I looked at, even with the better powders, the bullet is going to have a difficult time making it to 700 yards without falling transonic.
I have not tried any of this yet so its all just theory right now unless someone has shot out to 700 or beyond and stayed supersonic, then please tell us the secret sauce of how you did it. .

I think I will try this for the fun of it though.

Thank you all for the replies.

Look at the new eld-vt. Super high bc for a small bullet that you should be able to get going pretty fast.

 

[Haney]

Just no.

So much no..

Well said, you see some scary shit on here .

 

[Tex68w]

Although those are great for subsonic. Im not sure how the dead pig pictures at 200 yards helps, but thanks for posting and good shooting. On our land the setup is such that I mostly get a shot at deer and pigs between 200 and 250 yards. Its just laid out that way. But when you are used to shooting out to 1000 yards (not with 300blk) 250 yards is not a difficult shot.

Agreed, it's far from a difficult shot and those pics were with an unmagnified Eotech, so basically a red dot shot at 200, not bad considering. Our property is setup largely for shots inside of 200 which leaves almost every option on the table for small to medium game which is why the 300BLK sometimes takes a trip to the blind.

300BLK wasn't designed to be used for long range engagements, sure it can be done, but that's definitely not a strong suit for the cartridge. I guess I just don't understand why you'd want to try and stretch the legs of the 300BLK when there are so many other better options out there beyond 150-200?!

 

[tekmann2377]

This is an exercise in futility. Also many of suggestions here demonstrate a lack of understanding in terms of optimizing a cartridge of limited case capacity for long range use. For example, 200+ grain bullets will very significantly decrease the case capacity even if they provide a better BC. You will have to do the math and see what velocity a bullet would be capable of versus the available BC. I do agree this will likely be in the 168-175 gr range.

Forget about hunting with any of these loads as none of them will be at a reasonable velocity for dependable expansion, even right from the muzzle.

One thing I will tell you though is that for max velocity with heavier bullets, AA 1680 is your best friend. It is a dense, high energy powder that will make the most of the limited case.

 

[repiv]

"300BLK wasn't designed to be used for long range engagements, sure it can be done, but that's definitely not a strong suit for the cartridge. I guess I just don't understand why you'd want to try and stretch the legs of the 300BLK when there are so many other better options out there beyond 150-200?!"

I think you are missing the point. This was just a question for the sake of fun or seeing if it can be done. Please dont take this as something anyone would do to "depend on" or as a first option. Nobody would try to do this as a first option. Now that would be a really bad idea. Keep this is the realm of "for the fun of it". In my case I would be using a gun I already have and possibly load up a few rounds just to see what happens. No serious time or money invested.
Thanks for the input about 1680. I think that is what I will try if I get the time. I do think a 178Gr bullet at 1000+ plus fps would be OK though. To hunt ethically requires enough energy at given distance or otherwise is a no go.
I take the ethical hunting thing pretty seriously. Im not going hunting at 600 yards with a 300 blk.

 

[Clint H]

I think you are missing the point. This was just a question for the sake of fun or seeing if it can be done. Please dont take this as something anyone would do to "depend on" or as a first option. Nobody would try to do this as a first option. Now that would be a really bad idea. Keep this is the realm of "for the fun of it". In my case I would be using a gun I already have and possibly load up a few rounds just to see what happens. No serious time or money invested.

People get too uptight sometimes. It's a hobby. Have fun with it.

If NRL22 can exist and people can have fun taking 22lr out to 200yds+, you can experiment with 300blk and see what it can do.

 

[msgriff]

30 cal, AR-15, standard bolt, supersonic only, 150 Gr or less sounds like what Wilson designed the 300 HAM'R for.

 

[Hecouldgoalltheway]

You should play with it if you want to, but there are just so many better rounds out there that fit in an ar15 for distance. That's why I have a dozen ar15's I guess. I think that the 6.8spc is the best Eastern whitetail cartridge on the market. Out to 400y, it is devastating. The 6mm arc is 1,000y capable in an 18" barrel, kills mid sized game like a lightning bolt. The .22 nosler, 22 arc, and .224 Valk are superior to the .223 in every way except cost and availability, and there are really interesting wildcats out there, including several in the .25 variety. In most cases it's a barrel swap, worst case it's a barrel, bolt and magazine. Ar barrels are almost free and you can swap them in 10 minutes, or at least I can. There just really isn't much need to try to jam a square peg into a round hole, but if it's what you want to do, rock out with your cock out.

 

[Woodlanddude]

People forget that there is another "reason" to use the blackout that you want to maximize useable distance for. The sole reason I would pursue stretching the legs on the caliber. Suppressed/silent accurate fire. And for this it is not what most here would consider "Long Range". You will not get the same accuracy from a 308 that you will via the blackout. The inevitable dead space in the 308 cartridge for a subsonic load makes it inherently less accurate for sub loads (SD generally sucks), and pistol powders such as the donut shaped Trailboss are a compromise to achieve safety/reliability. Powders such as CFE blackout and others can give you sufficient case fill and not have as many safety issues for the 300 BO. You can shoot the same bullets as the 308 can subsonic, except with more accuracy and less fiddling to make it all work right. If the sole purpose is suppressed, you have a better tool now with the blackout using the same bullets available to run 308 subsonic. for my purposes it looks like around 300 would be the max sane range using a 16 or 18 inch barrel. (Yes you can get the same velocity for subs in a shorter barrel, but then stability/shootability of the platform for accuracy starts to matter IMHO). You could get about this far with the old 308 loads but generally with less accuracy, mainly due to twist rate of "issue" guns being 1/10 or 1/12 for 308/7.62, and the bullets required to reach stability. This usually also limited them to a 180 round nose load for stability. Standard twists for 300 BO usually get you as heavy as 308 goes or matters at the least (220 - 230).
A side note: A 16" 300 BO can absolutely get you 2350-2400 fps from the 110 V-max and 110 Barnes tac bullets. This keeps you over 1800 fps over 250 yards if I remember correctly. That gives it uses/options in addition to the subsonic. Not better options than other things, but we like options when selecting a tool, right?

 

[MSTN]

I wonder what the velocity increase would be using .300 BLK supersonic loads if the barrel had a 1x12 twist instead of the usual 1x7 twist.

 

[Clint H]

I wonder what the velocity increase would be using .300 BLK supersonic loads if the barrel had a 1x12 twist instead of the usual 1x7 twist.

It'd be interesting to test.

This article explored twist rate vs velocity with 308 and didn't find a large difference. Not sure if that can be applied to 300blk though with such a faster powder burn and smaller charge. Twist rate could have a bigger impact.

https://bulletin.accurateshooter.com/2022/05/how-muzzle-velocity-changes-with-different-barrel-twist-rates/#:~:text=Does%20muzzle%20velocity%20change%20with,loss%20is%20NOT%20that%20significant.

 

[Zigjib]

Not sure if this is going to help you, but we tested blackout out to distance (600y) and it was really consistent but you had to use good bullets. We were able to reliably, repeatedly and accurately engage a 12" steel plate to this distance. This was the max reliable range. After 600y, wind and all sorts of things really wreaked havoc. Some of the bullets were just insanely poor but the ones that stood out were the 125gr Nosler BTs, and 110gr V-Max. Absolute pick of the litter was unquestionably the 125gr Nosler. That bullet is exceptional. The really dissapointing ones were the 220gr SMK subs. In the wind drift chart, they have the highest BC so perform well against wind, but trying to keep them on the upper edge of subsonic.... man, the vertical spread was horrendous. The lowest mv was 720fps. Highest was 1200 something. No good at all.

We pushed these to 1000y.

Wind is what we use as a rough indicator of hit probability. This was through a bolt gun but for the shorter guns they were all Sigs or Warricks.

After testing, I ended up converting the 300blk bolt gun to an XM-3 build (had the right barrel length) and it's now a plinker for me.

I'm one of those people that thinks blackout is a dog shit round. DOG SHIT. We call it 30 Long Rifle. BUT. I'll never sell it or get rid of it. It's too fun to shoot. When you see that little round run out to 600y on steel. It's so satisfying.

 

[repiv]

That is some really good information. I appreciate you sharing this. I did some reading and playing around with different bullets and load data and from what I have read so far (no real world experience yet) the 174-178gr bullets pushed to the limits should yield good results. They might even get close to 700 yards before dipping below supersonic. I have not tried this yet but I think I will give it a shot next time I am at the farm.
The moving parts and barrel of the rifle in question are a JP Silent capture spring buffer (second lightest spring), JP Low Mass Bolt Carrier group, and a Proof Research carbon fiber 16" barrel with 1:8 twist. The gas block is fixed as I was running my adjustable gas block wide open to get function. The rounds will be handloads. I have a few other 300blk AR15s I can play with that have Wilson Combat or Faxon 16" Barrels if it helps. I think the goal of this will be to hit 700yards with decent accuracy. As you mentioned the wind may be the biggest factor to overcome.

I totally agree with you on the little round hitting Steele at distance. It just never gets old. There are people in here that get to shoot distance all the time. I only get to do it 5-6 times a year and mostly during hunting season. But the 4 second gap at 1000 yards from shot to hearing the "Gong" of the target is just so cool.

Thank you to everyone that posted in this thread.

 

[Zigjib]

That is some really good information. I appreciate you sharing this. I did some reading and playing around with different bullets and load data and from what I have read so far (no real world experience yet) the 174-178gr bullets pushed to the limits should yield good results. They might even get close to 700 yards before dipping below supersonic. I have not tried this yet but I think I will give it a shot next time I am at the farm.
The moving parts and barrel of the rifle in question are a JP Silent capture spring buffer (second lightest spring), JP Low Mass Bolt Carrier group, and a Proof Research carbon fiber 16" barrel with 1:8 twist. The gas block is fixed as I was running my adjustable gas block wide open to get function. The rounds will be handloads. I have a few other 300blk AR15s I can play with that have Wilson Combat or Faxon 16" Barrels if it helps. I think the goal of this will be to hit 700yards with decent accuracy. As you mentioned the wind may be the biggest factor to overcome.

I totally agree with you on the little round hitting Steele at distance. It just never gets old. There are people in here that get to shoot distance all the time. I only get to do it 5-6 times a year and mostly during hunting season. But the 4 second gap at 1000 yards from shot to hearing the "Gong" of the target is just so cool.

Thank you to everyone that posted in this thread.

I don't believe you'll achieve what you want to in the 178gr class bullets. We didn't specifically test the 178s as we found we were just running out of MV to make the heavier bullets work.
The blackout case has a small capacity to begin with. When choosing bullets, you have to decide whether you want supers or subs.
The long high BC bullets are great in 308, because you have the case capacity to drive them to the speed they need to do their job. That's not the case with the Blackout. The long HBC bullets eat up a lot of your case capacity. Especially when loaded to SAAMI spec. They have a long boat tail that precedes the bearing surface, so the bullets have to be seated deep even when you aren't limited to SAAMI. This means you just don't get enough powder to build up that MV.

This is where we sat on the 125grs. High BC (for that class bullet), great design so it gets through trans, isn't super long so we get enough powder. It was 100% the sweet spot. Looking at the results here. We were going off mainly factory ammunition. The Winchester Deer max was very good as well. I'm wondering if a 155gr ELD-M might be worth a look.

 

[357Max]

I'm wondering if a 155gr ELD-M might be worth a look.

See pist #3 above. The 155 eldn was the best Supersonic bullet I tested in my 8.5” BO.

 

[Zigjib]

See pist #3 above. The 155 eldn was the best Supersonic bullet I tested in my 8.5” BO.

Ah.... that's what I get for running my mouth before reading.

 

[HD1911]

We’ve taken them out to 385y and they still hit the steel pretty well. I wouldn’t wanna take one at that distance.

 

[Zigjib]

We’ve taken them out to 385y and they still hit the steel pretty well. I wouldn’t wanna take one at that distance.

We used the 800ft lbs as min requirement (deer) because in Aus, guns are scary..... but seeing as this forum is in the land of the fuckin FREE! 350ftlbs is seen as the minimum amount of energy required to cause trauma on a human being. With the 155s, you're good to 750m and it's still 340ft lbs at 800m so just sneaking under.

With the 125s is about 625m, so in this case, the 155s are better.

 

[HD1911]

that may have came out wrong… I meant I sure wouldn’t want to be on the receiving end of it even at distance.

 

[Zigjib]

that may have came out wrong… I meant I sure wouldn’t want to be on the receiving end of it even at distance.

nah man, i'm hearing you, just thought i'd put up the deets based on the Ballistic app.

 

[coldboremiracle]

People forget that there is another "reason" to use the blackout that you want to maximize useable distance for. The sole reason I would pursue stretching the legs on the caliber. Suppressed/silent accurate fire. And for this it is not what most here would consider "Long Range". You will not get the same accuracy from a 308 that you will via the blackout.

Can confirm. One of my favorite projects is trying to accurately shoot subsonics at longer distances. I've shot SS 308 out to like 480, and while it was useful (220RN) at that distance, I wouldn't call it accurate. Upping the weight of projectiles seems to increase effectiveness. I also tried 450BM subs, using (swaged down .458's) 405 grain bullets, and they are very reliable (sub 1.5MOA) out to around 200 yds. And still very useful at 300. The sound of these bullets hitting the side of deer is much louder than the gun going off.

 

[45-90]

If I was gonna shoot game at longer range, with the dual purpose cartridges sub/ supers line, like the 300 BO....but concentrated on supers only I go with a larger cartridge, like the 8.6 BO with a 6.5 twist and the longer barrel. Mine shoots the 160 Barnes at 2800 fps. 300 gr high BC match 1975 fps. 350 gr Maker at 1700 fps.

A 338 RCM in 18" AR 10 would work too, a 200 gr bullet at 2700 fps, accurate and fast enough with the energy needed, for any game in N America, 250 grs at 2550 fps for large bears.

Or a boltgun in 510 Whisper if ya want more than 2000 ft/ lbs at 1000 yds, with 1002 gr bullets, or a 350 gr segmented copper bullet at 2450 fps for 4700 ft/ lbs.
The 750 Amax at just 1500 fps carries really well and brings alot of energy.
Plus you'd have APITs at your disposal for piercing that armor tough hog hide, and set off the the exploding tips on the heavy bone....cool.
I have all of those calibers, but wouldn't consider my 300 BO as a moderate range big game killer.
The 300 Hamr is a better super only AR 15 cartridge, my 18" is light handy, & accurate..but it doesn't shoot high BC bullets and would lose energy fairly quick.

 

[Woodlanddude]

All the above are valid and true. Cost/Availability of the other calibers is, however, prohibitive for many and requires much more specialization of equipment and components. The beauty of the 300 is the compatibility of components and equipment with 5.56 and .308. With 300 BO, you slap a .30 cal 8 twist barrel on ar-15 upper or 5.56 faced bolt gun and run it. Brass can be easily converted from LC 5.56 picked up at the range. None of the above were available when the BO hit the market strong. 300 BO gives SOME capability of the above with minimum buy in. For most, a decent recce style AR upper is the sweet spot to try it out. Though some find it lacking in power, the 110 and 120 Tac TX have a lot of impressive kills on everything from deer to elk and bear (not my recommendation). If you have the resources, there is definitely better out there now. If not, why not the 300? More ammo and trigger time is never a bad thing with the gun you an afford.

 

[Tailwater]

Not sure if this is going to help you, but we tested blackout out to distance (600y) and it was really consistent but you had to use good bullets. We were able to reliably, repeatedly and accurately engage a 12" steel plate to this distance. This was the max reliable range. After 600y, wind and all sorts of things really wreaked havoc. Some of the bullets were just insanely poor but the ones that stood out were the 125gr Nosler BTs, and 110gr V-Max. Absolute pick of the litter was unquestionably the 125gr Nosler. That bullet is exceptional. The really dissapointing ones were the 220gr SMK subs. In the wind drift chart, they have the highest BC so perform well against wind, but trying to keep them on the upper edge of subsonic.... man, the vertical spread was horrendous. The lowest mv was 720fps. Highest was 1200 something. No good at all.

We pushed these to 1000y.

Wind is what we use as a rough indicator of hit probability. This was through a bolt gun but for the shorter guns they were all Sigs or Warricks.

After testing, I ended up converting the 300blk bolt gun to an XM-3 build (had the right barrel length) and it's now a plinker for me.

I'm one of those people that thinks blackout is a dog shit round. DOG SHIT. We call it 30 Long Rifle. BUT. I'll never sell it or get rid of it. It's too fun to shoot. When you see that little round run out to 600y on steel. It's so satisfying. View attachment 8466406View attachment 8466395

What barrel manufacturer are you using for these tests. Is there a right answer to the question of which barrel manufacturer produces the most accurate result, all else being equal?

 

[Zigjib]

What barrel manufacturer are you using for these tests. Is there a right answer to the question of which barrel manufacturer produces the most accurate result, all else being equal?

This was done as part of a use case report. The guns had factory barrels fitted except the 18.5" which was custom. The blackout was being assessed in conjunction with the rifles. There are manufacturers that make better barrels than others but this largely comes down to how many burrs are present in the barrel, twist rate consistency and bore diameter consistency WRT how they are made. Fit and finish is on the smith that fits them. It's a little outside our ballpark as we weren't going to DQ a system based on how the barrel is made as the accuracy requirement wasn't there from the customer. We needed energy and we needed to know what barrel length and bullet combination worked. All else was on them to decide what gun fit the bill. If you want to know specifically about test barrels for t/e of projectiles, message Frank Green. Dudes super knowledgeable and a good bloke

 

[45-90]

All the above are valid and true. Cost/Availability of the other calibers is, however, prohibitive for many and requires much more specialization of equipment and components. The beauty of the 300 is the compatibility of components and equipment with 5.56 and .308. With 300 BO, you slap a .30 cal 8 twist barrel on ar-15 upper or 5.56 faced bolt gun and run it. Brass can be easily converted from LC 5.56 picked up at the range. None of the above were available when the BO hit the market strong. 300 BO gives SOME capability of the above with minimum buy in. For most, a decent recce style AR upper is the sweet spot to try it out. Though some find it lacking in power, the 110 and 120 Tac TX have a lot of impressive kills on everything from deer to elk and bear (not my recommendation). If you have the resources, there is definitely better out there now. If not, why not the 300? More ammo and trigger time is never a bad thing with the gun you an afford.

If your stuck on the 300 BO super and light bullets 110 to 120 gr the 300 Hamr is your ticket. Brass is slightly easier to form out of 5.56, uses the same components as the 308, or 300 BO.
But the 300 Hamr gets more velocity, my 18" gets 2766 fps with the 110 gr Barns, & AA 1680...
Or 125 Accubond to 2509 fps to 2589 fps depending on loading factors, it has a fair BC and more weight.
150 gr gold dot 2386 to 2400 fps
150 gr Speer BT hot cor 2303 to 2398 fps and produced a 5 shot .264" group at 100 yds.
Seems like the 300 Hamr would be your best tool for the job to meet your requirements. I have both, an 18" fluted Hamr would be the ticket.
I also have an AR 10, that's 6 lb, with 16" barrel in 308 .
Has carbon fiber, titanium, and magnesium for the upper, that's 1/2" MOA 5 shot capable with 168 eldm at 2756 Ave fps...lighter than the AR 15. But it's an expensive build.
The 300 Hamr is your ticket. I have load data.