View Full Version : 300 BLK Zeroes and Trajectories
There is a wealth of knowledge on the 5.56 side of the house, but not as much here. Does anyone have any information on the various trajectories from shorter barrels? I have zeroed my 8.5 @ 25 yards with 220's, but am looking for some sort of knowledge base. I will primarily be shooting 220's, with 110's for hunting.
I've been searching for similar info. I have a 9" and shoot 220s and 110s but haven't found good zeroing info.... and don't want to spend the $ finding my own ballistic info.
If you are good with software, you can chrono your gun, get the BC info from the bullet manufacturer website, download the Point Blank application for Windows and play around with the zero ranges until you find one that works.
I don't have a 9" barrel yet, but going off of what has been published by rsilvers and grabbing the BC from Barnes website, it looks like you can get a good zero at 100 yards for supers. You'd be -0.23 at 50, -7.46 at 200, and -27.65 at 300. And you'd never have to hold under.
But that's probably different than what you'd get. You really want to chrono your guns to be sure.
Question is how far do you want to go?
I Shot a 300 about 2 months ago. I was running a 16" barrel. Not exactly the info that your looking for.
Prone bipod shooting at 350ish something yards shooting freedom ammo 140 something grain bullet. Rifle was home built job. With questionable parts in my opinion.
Point being is it was almost impossible to get consistent hits on steel. I remember I had around 40 inches of hold or something like that.
I won't say it's impossible, but shooting that distance, from what I saw, using that one time as my only experience with 300, is going to be a real tall order.
Have you looked at 300blktalk.com? They have a lot of that type of info there.
Sent from my iPhone using Tapatalk
Use JBM Ballistics. Input data and make yourself a chart.
domestique
05-03-16, 11:02
https://www.m4carbine.net/showthread.php?103421-300blk-zero
https://www.m4carbine.net/showthread.php?103421-300blk-zero
I.e. 110 gr. Black Tip.
As for drop - use a 200 yard zero. You can shoot out to ~237 yards with no scope adjustments and it will be about 3.5 inches low at that range and never be more than 3.5 inches high.
Curious myself. I have a 8.5" barrel on mine, also zero'd at 25 since it's my HD gun, and i shoot 220s and 110's with a suppressor. I have a magnetospeed chrono, so i'll do some testing and see what charts I can put together. I've been thinking about doing it but haven't had the time yet, but hopefully this weekend will work
The PRO on my suppressed 8.3" is zeroed with 110s at 25 yards. From what I've read, that leaves me pretty close out to 150 yards. It's primarily used as a HD gun and occasional hunting (within 100 yards).
Good stuff. Any info on the 220's. I don't plan on shooting past 200, and I wonder if there isn't a good medium for one zero that covers both supers and subs.
Good stuff. Any info on the 220's. I don't plan on shooting past 200, and I wonder if there isn't a good medium for one zero that covers both supers and subs.
No.
With my 10.3" I have a 10" spread between subs(220gr) and supers(110-125gr) at 100 yards. I have not shot subs past 100 nor do I intend to.
Sent via telegraph with the same fingers I use to sip whiskey
Thanks, that's what I thought. Ditto on the 100 yard subsonic range.
SWATcop556
05-05-16, 16:05
For those who are zeroing at 25 yards I hope you are shooting past that to confirm any necessary hold overs.
My AAC 9.5 is zeroed at 100. I hit about 1.5" below POA at 50 and about 6.5" at 200 shooting 110 supers.
Its a niche gun but I have a need for it and it works very well for its intended purposes.
friendlyfireisnt
05-05-16, 16:54
Its a niche gun but I have a need for it and it works very well for its intended purposes.
Any chance you can tell us about the niche or purpose for it?
I know I have my own reasons for the .300blk (specifically the 110gr Blacktips). But I am always curious about others.
Thanks.
ETA:
Right now I have my 10.3" .300blk zero'd @ 100 yards. Based on JBM's #'s that puts me damn close to 175 yards, 1/2 a foot low at 200 (7 inches my but who's counting), 1 ft low at 250 (15") and 2 ft low at 300 (26"). I may not be able to remember the exact inches of the drop, but I can remember 1/2, 1 & 2.
I am debating on switching to 35 yard zero, but haven't committed yet.
Disregard. Not directly related to zeroes and trajectories.
I would not say that it is a niche cartridge. When you look at component stresses, strains, erosion, etc.. The 300 Blackout can have advantages for many going less than 11.5" in an AR base platform compared to 5.56.
daddyusmaximus
05-13-16, 21:13
I'm getting in the .300blk game as of today. My gunsmith ordered the Wilson Combat 11.3" barrel for my old 9.5" SBR upper. For close range shooting like home defense/SHTF patroling (what this will be) everything I have read gives the advantage to the .300blk over a 5.56 in a SBR. Now my shortest 5.56 will be 16".
I was playing around some more with the JBM calculator.
If you grab the default data for the Hornady 110gr V-Max (a very common round for Blk), and grab the published 9" V-Max numbers from AAC, then the JBM calculator gives you the following:
Maximum PBR: 256 yd Maximum PBR Zero: 220 yd
It first crosses the line at 25 yards. So it looks like a 25 yard zero confirmed at 220 is a pretty good way to go.
If you want to zero for the top of the arc so you never have a hold-under, that looks like 80 yards.
Eurodriver
05-18-16, 09:28
I had an AAC 9" 300BLK. It was zeroed at 220 yards (not 25 and "guess its ok at 220"). This was with 110gr Barnes handloads. My issue with the round was the POI issue between supers and subs (subsonic cycling is the only true advantage of the round for me). Using a T1 there was no really good zero that worked well for both, and a T1 isn't easily adjustable.
Additionally, the round drops like a rock beyond 250 yards even out of a 14.5" Noveske. Out of a 16" barrel, 110gr Barnes will drop 100" at 500 yards while Wolf Gold out of an 11.5" 5.56 drops less than 80". It gets even worse if you use quality 77gr out of the 5.56.
For me, it wasn't worth having to store the additional caliber so I sold it. Took six deer with it though...still have love for it. ;)
If you know your dot size and use it, you can make quality hits quickly out to 250 quickly out of the PDW sized package. You can stretch it longer with a little more time. It's not that hard or really slow, just not as quick as a simple possible double in dot size offset.
I would prefer another option for a 500 yard application and beyond. Those would not be PDW sized. Sure, I've made good hits on target easier with more barrel length in 5.56, but you may sacrifice close in use.
For closer in targets that would more than likely cover most users of a PDW type of platform, I would still lean towards the 9"-9.5" Blackout over the same barrel length in 5.56 or 9mm for use at the distances here.
Eurodriver
05-18-16, 18:28
No doubt as a PDW with a 9" barrel the 300blk wins. It wins solely on the fact that 5.56 is a nuclear bomb out of barrels that short. And if you're shooting within a hundred yards it's legit kit.
My issue is distance. I still have not found where in the hell these people hunt, because aside from one dumb Buck who was too busy eating to look up as I walked around a tree, all of the deer I have shot at (or even seen) have been beyond 250 yards. And when you're hunting out of state and don't bother with the SBR permission slip the 16" 5.56 is going to give you much easier hits because it drops less.
Even in the PDW role, it can be damn near 300 yards from one end of a Walmart to the other. A 9" 300 is dropping what? 6 feet at that distance? And maybe 2 feet for every 50 yards thereafter. Which means if you aim at the chest and your range estimate is 50 yards off your round will go right in between his legs or over his head.
I wish there was a flatter flying 300BLK. I'd be all over that jazz. All. Over. It.
I would prefer not to shoot 5.56 over 300 blackout in less than 11.5" barrels.
I don't know where you hunt, but most here (Missouri) seem to be 33 or less yards.
I don't hunt at Walmart, but I understand the the analogy.
I understand the non SBR issue when crossing state lines. That does not mean the alternatives are more effective.
What is 6' for 300 yards with a 4 MOA dot? What is your hold over? It's not hard to look it up?
I ran a few with 1.1-8x MK8's, hold overs with the Horus can work really well. Sub's and super's can be paired up without adjustment. Just adjust your impacts for the corrections in the Horus grid. That optic is heavy for the PDW, but some sound results can be had knowing those with a simple red dot, knowing the size.
Most would never need more than the red dot to use to help know the offset if they know the impacts.
friendlyfireisnt
05-18-16, 21:35
Even in the PDW role, it can be damn near 300 yards from one end of a Walmart to the other. A 9" 300 is dropping what? 6 feet at that distance? And maybe 2 feet for every 50 yards thereafter. Which means if you aim at the chest and your range estimate is 50 yards off your round will go right in between his legs or over his head.
I wish there was a flatter flying 300BLK. I'd be all over that jazz. All. Over. It.
I'm trying to figure out where you are getting 6 feet of drop at 300 yards from?!?!
Currently, I'm zero'd .5" high @ 100 yards with 110gr Blacktips out of a 10.3" barrel.
I can hold dead on out to 175 yards. I am 6 inches low at 200 yards. I am 13.6 inches low at 250 yards. I'm 24.8 inches low at 300 yards. So my holds are simple. Dead on out to 175, 1/2' @ 200, 1' @ 250 yards, 2' @ 300 yards.
Not soo bad, and pretty easy to remember actually.
Eurodriver
05-19-16, 06:28
My deepest apologies gentlemen, I had my 500 and 300 yard data mixed up. (220yd zero with 110gr Tac-TX @ 2400 FPS drops 78" at 500 yards.)
There is a lot going for the 300BLK, no doubt. After looking at the numbers harder with different zeros and 5.56 loads, it gets even better. (Remember, I had one and used one so I'm not anti-300BLK ;) ) If I didn't mind the hassle of storing another cartridge it'd still be in my safe, but for what I do 5.56 and 308 suit my needs better than an intermediate cartridge.
Tom, 33 yards for hunting? Crazy!
I agree with you on the intermediate cartridge vs 308, etc... The only reason I went that direction is it provided me with the cheapest suppressed SBR solution that also offered me great reliability. Is is also BALLS accurate.
As one who hasn't jumped on the Blackout bandwagon yet, I'm more interested in the improved performance of the .30 cal AR than I am about subsonic rounds. I've got no use for them. There was a writeup recently on the Firearms Blog about the .300 Uronen from Finland in which the designer used the .221 Fireball case to get more velocity. He also used a slower barrel twist since he wasn't shooting heavy subsonic bullets.
It got me wondering about making a .300 BLK-ish weapon idealized for supersonic bullets only. Handloaders and specialty ammo makers could roll their own higher performance ammo but standard supersonic .300 blk could still be utilized for cheaper ammo options.
ramairthree
05-19-16, 23:58
Off the top of my head my 220 loads are right at 1000fps.
I built a 16 inch gun.
It uses the bower CAC suppressor I had on my M11 before I sold it.
The non subs I use without the suppressor are made from pulled ammo and run about 2000 fps.
I could get faster dropping down to 110s but that pulled bullets are what I have a ton of.
Being on at 100 with the
Subs is an inch or two low up close, a couple of inches high in between, and I think drops five or six at 125. Not really any use past that.
I think the same zero puts me about an inch or two high at 100 and six or more low at 200.
This is off the top of my head.
There is no great zero for my subs and supers to use together.
With 110s you will have an ever bigger drop in velocity to shift things when you throw in your subs.
I was working on this particular problem last year - I just did a short write up on LF.net you could check out.
http://www.lightfighter.net/topic/red-dots-300blk-and-bdcs-a-quandry?reply=30580333420163050#30580333420163050
In short, using the 30/200yd zero for the 110's give me a usable zero for 194gr ME Lehigh subsonics out to 100m. There is a pretty kickass little red dot available where the reticle subtensions line up for those loads just about perfect.
For the 220gr subs you asked about, they can be used with that sight also on one of the BDC dots. Check out the LF post - it might help some
Disclaimer: Keep in mind, the POA/POIs referenced in my LF post are not up to snuff for precision long range - they are "close enough" for an 9.5" SBR with an RDS on a man/pig sized target.
domestique
05-21-16, 10:08
I was working on this particular problem last year - I just did a short write up on LF.net you could check out.
http://www.lightfighter.net/topic/red-dots-300blk-and-bdcs-a-quandry?reply=30580333420163050#30580333420163050
In short, using the 30/200yd zero for the 110's give me a usable zero for 194gr ME Lehigh subsonics out to 100m. There is a pretty kickass little red dot available where the reticle subtensions line up for those loads just about perfect.
For the 220gr subs you asked about, they can be used with that sight also on one of the BDC dots. Check out the LF post - it might help some
Disclaimer: Keep in mind, the POA/POIs referenced in my LF post are not up to snuff for precision long range - they are "close enough" for an 9.5" SBR with an RDS on a man/pig sized target.
How has the sight held up over the last year?
Worth the 400+ price tag?
ETA: The company is based in the UK, but I couldn't confirm if they are made there, or CHICOM made.
ETA #2: A little more digging, the British MOD actually adopted the SIS CQB to piggyback on the Elcan's the SAS are running.
It's done fine for me - granted I've only had it since about January and my use has only consisted of range trips. Not exactly torture testing.
In terms of value, it was worth the money to me to have one RDS that could handle both my supers and subs without adjustment. I haven't bought a micro Aimpoint in a while, but I don't recall them being any less expensive than the price on the Shield. I typically run Aimpoints, so the money is what it is.
I'm not sure where they run their manufacturing, but you're right - the company is out of the UK.
What is the max Rise using the 30/200 zero? what is the deviation at 100 using the 110's?
I was working on this particular problem last year - I just did a short write up on LF.net you could check out.
http://www.lightfighter.net/topic/red-dots-300blk-and-bdcs-a-quandry?reply=30580333420163050#30580333420163050
In short, using the 30/200yd zero for the 110's give me a usable zero for 194gr ME Lehigh subsonics out to 100m. There is a pretty kickass little red dot available where the reticle subtensions line up for those loads just about perfect.
For the 220gr subs you asked about, they can be used with that sight also on one of the BDC dots. Check out the LF post - it might help some
Disclaimer: Keep in mind, the POA/POIs referenced in my LF post are not up to snuff for precision long range - they are "close enough" for an 9.5" SBR with an RDS on a man/pig sized target.
My understanding is the max is about 3 inches + (per the info from R. Silvers here: https://www.m4carbine.net/showthread.php?103421-300blk-zero)
At 100, my 110s were right at 3" high.
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