Barnes 70 TSX zero

[karlglen101]

Has anyone attempted the IBZ 50y/225m with the Barnes 70 TSX? I know this zero is suited to a 55gr. bullet but thought that it would come close. I took a couple of shots at a coyote around the 220y mark and it dropped right at his feet. I had zero'd at 50y, and tested it at 100y where it hit a little high as I expected it to - similar to an XM193 55gr. I assumed it would be close to the same (but knew it would be a little short) at the 200-225y mark. I was pretty surprised it dropped so much. The other added factor was my SDN-6. I was dialed in for the 50y, and also tested at 100y. It was consistent to what I had zero'd and tested without the can. However, I'm wondering if it has a greater impact on the bullet's trajectory at further distances - or if the bullet just drops a lot harder than I was expecting it to.
I need to find a 200 yard range to answer definitively, but wanted to know your thoughts. Thanks.

edit: I've loaded these over 24 grains of Varget.

[Onyx Z]

What velocity are they loaded to? Barrel length? I would confirm your zero at 200yds if that range is available.

Check out the shooter app on iPhone and Android. It calculates ballistics for you.

[karlglen101]

I don't have a chrono. It's a 16" DD 1/7 twist barrel. I will eventually confirm on a 200 yard range, but I don't have one close. It's over an hour's drive. I will for sure get there sometime next year when it gets warm =)

I will look into that shooter's app for Android, thanks for the tip!

[HD1911]

Just ran the Numbers on my KAC BulletFlight real quick, on my phone... only figuring on 2,700 FPS on that 70gr TSX, zero'd Dead Nuts @ 50 Yards, you should be 2" Low @ 225Y. Not nearly low enough for a Miss if you're sure you broke the Shot Correctly. The important part of this equation is finding out just how much POI shift you're having at your 50 Yard Zero, with that 70gr TSX Load, when the Can is mounted. My guess is that's the Culprit. Combine 2" Low Trajectory with a nice POI Shift Downwards when Can is attached, and Voila'.

[karlglen101]

Thanks for running that. Those numbers are kind of what I expected. I really believe the can had a greater impact. I dialed in my numbers at 50 yards and wrote them in my book so I could just switch with the can off and on. I took my sweet time with this shot as I had missed him earlier when he was slightly on the move and I thought that one was me, but I normally don't miss the easy ones like this. However, when the second one dropped too I became suspect. For the second shot, I tracked him for 30 yards coming towards me, and waited until I didn't think he would come any further before breaking the shot.
At 50 yards, my group was significantly low, but consistent with the can. Roughly 4" low and a .5" left. As I said before, I'll ultimately riddle this out on the range but wondered if anyone else has had a similar experience with the 70 TSX or ever test fired it for the IBZ. I have followed Skypup's thread religiously, and noted that he normally zero's for 100 yards. I will do the same for this round next year.

[HD1911]

Just to Rule out these Variables.... What Optic/Mount are you utilizing btw? Are we sure they're squared away and holding zero? What are your Groups like with this Ammo?


w/ 50Y Zero: 29756




w/ 100Y Zero: 29757


4" Low @ 50y once the Muffler is mounted, is huge at 225y. If you didn't compensate for that, when shooting at the Yote' @ 225Y, that's the Culprit, plain and simple.

I wouldn't be looking at the Bullet at all, or the Trajectory for that matter... rather your POI Shift and lack of comensating for that @ 225Y is why the Bullet impacted soo low.

If you know you're going to be attempting a killshot with the Can attached, then what should've taken place was a Confirmed Zero @ 50 Yards, with that Exact Load, with the Can Mounted.

Did I assume too much right there? If you knew that your Zero would be off by 2.2 Mils once the Can was mounted, and dialed that for the shot, then your 50 Yard zero without the Can would've been fine, since you would've compensated for the Low POI Shift... and the 2" Low due to that Loads Trajectory would've been nothing.... provided that obviously your POI Shift was Consistent.

btw 4" Low on your Zero @ 50 Yards, which is 2.2 Mils, puts you at being 17.8" Low @ 225Y (because of POI Shift w/ Can attached), then add in the 2" Drop from the Trajectory... that puts you at about 20" Low when you fired that shot... does that sound about right, concerning what happened in the Field?

[karlglen101]

HD1911 - Thanks. I have given those factors consideration as well. I am shooting a Burris Fullfield II 3-9x mounted in a Burris PEPR mount. I'm fairly confident the zero held true. I zero'd without the can, using X193 at 50 yards. I normally do this as my main use for the rifle other than range time, is shooting multi-gun / 3 gun. The IBZ holds true and I ring 200 yards with it. After the 50 yard zero of XM193, I then run a 5 shot group with my Barnes load. It was really close, just a tad low. I only had to fine dial it about .5" @ 50y. The next range trip was for a cold bore shot with my Barnes round. It was dead nuts at 50y, maybe 1/4" below the bull at 50y. The next range trip is when I took the can. To verify my zero held true, I ran some XM193 to warm up the barrel, followed by a 3 round group of the Barnes to confirm it was still on and it was. The final trip to the range before hunting this past weekend, was to try out the can. It was my first and only time shooting it before hunting. I can't legally hunt with it, but took it just for the hay of it. With the can on, it dropped considerably. It was 18 clicks to bring point of impact up and zero'd with the can. After zero with can, I removed it, and dialed back down, and verified my zero was on. When I saw the yote, I threw the can on and dialed the scope in.

Ultimately, I think this round drops much further than I expected. I knew the IBZ was not going to be right on, but I think it's further off than I anticipated.

[HD1911]

HD1911 - Thanks. I have given those factors consideration as well. I am shooting a Burris Fullfield II 3-9x mounted in a Burris PEPR mount. I'm fairly confident the zero held true. I zero'd without the can, using X193 at 50 yards. I normally do this as my main use for the rifle other than range time, is shooting multi-gun / 3 gun. The IBZ holds true and I ring 200 yards with it. After the 50 yard zero of XM193, I then run a 5 shot group with my Barnes load. It was really close, just a tad low. I only had to fine dial it about .5" @ 50y. The next range trip was for a cold bore shot with my Barnes round. It was dead nuts at 50y, maybe 1/4" below the bull at 50y. The next range trip is when I took the can. To verify my zero held true, I ran some XM193 to warm up the barrel, followed by a 3 round group of the Barnes to confirm it was still on and it was. The final trip to the range before hunting this past weekend, was to try out the can. It was my first and only time shooting it before hunting. I can't legally hunt with it, but took it just for the hay of it. With the can on, it dropped considerably. It was 18 clicks to bring point of impact up and zero'd with the can. After zero with can, I removed it, and dialed back down, and verified my zero was on. When I saw the yote, I threw the can on and dialed the scope in.

Ultimately, I think this round drops much further than I expected. I knew the IBZ was not going to be right on, but I think it's further off than I anticipated.

You're quite welcome, sir.

You able to shoot @ 50 and 225 again and confirm what the 70gr Round is doing? The bullet on target don't lie. I think you'll change your mind about a 50Y Zero with this 70gr TSX.

With almost any Cartrdige/Caliber/Load out there, a 50y zero should put you back on around 200ish yards, with drop generally not being more than 2", and in some cases dead on... so my point is, if that 70gr Load is Zero'd on Target @ 50 Yards, there's no way it's dropped more than a few inches @ 225 Yards. Something else happend.....if you had the reticle on his front shoulder area, and yet the round impacted at the ground on his feet.... either you miss-dialed (which can easily happen under adrenaline and the heat of the moment, believe me) to compensate for the Low POI w/ Can being attached, you broke the shot terribly (which you said you didn't), or your Optic/Mount let you down.

Thoughts?

[karlglen101]

I hear you. I know it's got to be one of those factors as well. I have not yet had a chance to make it to the range. It will be quite some time before I can. I will assuredly report back once I do. It is very possible that I mis-dialed after threading the can back on.

[Onyx Z]

Did you have a clean bore before going hunting? Due to the full copper construction of Barnes bullets, they require a copper free bore for consistent accuracy. Put a different bullet down the barrel before the Barnes and there's no telling what will happen.

Also, 50yds is not nearly enough to determine the accuracy/200yd zero of any given bullet. You could probably run hundreds of Barnes bullets through a barrel and you wouldn't notice a difference at 50yds. 100yd you will see a noticeable difference, further than that and it gets exponentially worse. You say you put M193 down the bore before shooting the TSX... from my experience, different powder residue in the bore makes a big difference in consistent accuracy.

Start with a clean, copper-free bore and clean/remove copper every few shots. This is the reason I have been putting off load development on these bullets. IMR came out with a new powder that is temp stable AND has a copper fouling reducer that I will be testing in the coming weeks. Hopefully this works well with these bullets.

[HD1911]

I hear you. I know it's got to be one of those factors as well. I have not yet had a chance to make it to the range. It will be quite some time before I can. I will assuredly report back once I do. It is very possible that I mis-dialed after threading the can back on.

I'm definitely interested to find it out.... I would say it most likely, and agree with you, that you mis-dialed... it happens.

Run a Box Test on your Optic and make sure it's tracking and returning to zero after being significantly Dialed Left, Right, Down, Up. That'll confirm if it's good or bad. Good test to do on any Optic to make it proves it's worthiness.

[karlglen101]

No, I didn't clean the bore. I don't clean the bore during season once I've zero'd. Before this weekend, I've only put 8 rounds of the Barnes through it (this season). I did the same last season as well. I've never tested it out to 200+ prior to this weekend. My deer last year was about 100y on the spot and my POI was pretty much right where my POA was (within 2-3"). The deer moving a bit, my adrenaline, etc. played a factor.

[HD1911]

I've never seen a shift or lack of groupings due to different powders and bullets going down the pipe.... what I have noticed is when the bore is squeaky clean and cold, there is a shift. No bullet likes to be going down a Clean, Copper Free Bore. That is a recipe for your first shot or two being significantly outside of zero...especially while in the field, when you need it to count the most... that's a No-Go.

[Onyx Z]

I've never seen a shift or lack of groupings due to different powders and bullets going down the pipe....

This is ONLY for Barnes all-copper bullets. Any match bullet, FMJ, etc. don't require this as they have a gilding metal (95% copper, 5% zinc) jacket. A cold bore shot is a whole different animal.

[HD1911]

This is ONLY for Barnes all-copper bullets. Any match bullet, FMJ, etc. don't require this as they have a gilding metal (95% copper, 5% zinc) jacket. A cold bore shot is a whole different animal.

I didn't know the Barnes were special in that regard...... here's my point though: on a BCM SS410 16" and a Novekse N4 Light Barrel, I can share multiple Zeros between these Loads: M193, M855, Mk262, FGMM 77gr, AE .223 55gr, and BH 5.56 Barnes 50gr TSX, and all are within 1" of each other @ 50 Yards, and at 200 Yards I can consistently hit 8" Steel Plates, all day long... with all of those Loads, without ever adjusting or dialing anything.... and this is with an Aimpoint T1.

I don't think what you're saying really makes that big of a Difference. Not enough to drop a shot 10-20" Low @ 225Y.

[Onyx Z]

Here's a thread that discusses these bullets in depth. The later pages have discussions about the need of the clean barrel:

https://www.m4carbine.net/showthread.php?94628-223-Barnes-70-Grain-TSX-Performance

I don't know the physics behind the all-copper vs jacketed bullets and the copper fouling, etc., but I have seen a 2-3moa difference in a clean barrel vs a fouled barrel with these bullets.

[HD1911]

Here's a thread that discusses these bullets in depth. The later pages have discussions about the need of the clean barrel:

https://www.m4carbine.net/showthread.php?94628-223-Barnes-70-Grain-TSX-Performance

I don't know the physics behind the all-copper vs jacketed bullets and the copper fouling, etc., but I have seen a 2-3moa difference in a clean barrel vs a fouled barrel with these bullets.

I'll take a peek at that thread. Yeah a 2-3 moa jump is pretty serious for sure.