Irregular Drop 6.5CM at 200 yds

[bulldog87]

Keep in mind I'm newish to reloading, I know a little about a lot. Thanks in advance.

Loads:
143g Hornady ELD-X
Hornady Brass
Winchester LR Primers
H4350 39.5 gr (8 inches of drop at 200yds) Superperformance 43.1 gr (9 inches of drop at 200 yards)
OAL: 2.800 which is what the book calls for, haven't done anything off lands yet
Had very good accuracy with both loads, just the ridiculous drop with both. What in the world is going on?

120g Hornady GMX
Hornady Brass
Winchester LR Primers
OAL: 2.700
Superperformance 46.4gr (which ends up being a compressed load) Around 2.5-3 in of drop (200 yds) from what I've shot. But didn't get to shoot them much at all to confidently say a average number. 2.5 inches would be the proper drop in ballistic calculator, so I'm close with this load.

The first 40 bullets shot through the gun where Sig Sauer Elite Hunter 130gr (got them for 26 bucks on Black Friday) drop was less than 3 inches, sub MOA accuracy at 100 and 200yds

I have no problem with this load considering I want to hunt with the GMX next year, but I want to be able to shoot my 143gr as well because I have a 100ct ready to load. Plus my grouping at 100 and 200 with the 143 was sub MOA, much better grouping than GMX but I can't even begin to think about shooting 300 yards with there 143 round because I have no idea what's going to happen. The end goal is to shoot decently at 800 yards. Keep in mind, if I figure out this issue with the 143, I am still probably switching to the 130 eld match to send lead down range. I originally bought the 143 for hunting this year and I did shoot my 8pt with them I just didn't like how I didn't get a pass through with a clean double lung at 200 yards (why I am switching to GMX) and yes I had to aim at the top of its back to accommodate for the drop I was experiencing) However, this problem frustrates me. I've never experienced this problem, ever. Loaded 270, 243, 223, 22-250 with various weights and have never experienced anything like this. This is just going over my head. (I'm also buying federal 210m primers tomorrow to get a better primer, wonder if primers could be a issue?) And no I haven't shot through a chronograph. Regardless of switching bullets down the road, I do want to figure this problem out and would love to load those bullets and send them down range instead of collecting dust.

Note: Seems to have more than normal amount of powder where the bullet seats when I look with a bore light?
Gun: Model 700 ADL Tactical, Heavy Barrel 24", 1:8

 

[Mike Casselton]

Do all of those loads hit to the exact same verticle impact point at 100yds.

I'd put good money on the answer being no.

Different bullets will have different impact points based on weight, velocity and even the barrel's position as the bullet is released from the barrel.

 

[Doom]

Both of your loads seem low based on Hodgdon ( I don't have Hodgen's latest loading manual) data and the drop is telling you the velocity is way down. What you are seeing on the necks is carbon and is also an indication of low pressure and the neck not sealing.

NOTE: I am assuming you are referring to a true drop (meaning you are zeroed at 100yd with the 143) from 100yds to 200 yds,

 

[bulldog87]

Both of your loads seem low based on Hodgdon ( I don't have Hodgen's latest loading manual) data and the drop is telling you the velocity is way down. What you are seeing on the necks is carbon and is also an indication of low pressure and the neck not sealing.

NOTE: I am assuming you are referring to a true drop (meaning you are zeroed at 100yd with the 143) from 100yds to 200 yds,

Yes, true zero. I’m about about 3/4 max load on everything according to Hornady manual. If I seat the 143 further could that fix the problem? Am I losing too much pressure you think?

 

[ditter]

To get an 8 inch drop from 100 to 200 yards, your MV would have to be 2000 fps. And that's not 39.5 grains of 4350.

 

[2aBaC̶a̶]

Let me get this right.

Scope zeroed at 100, leaving turrets at 0 and holding the crosshairs on a bullseye at 200 gives impacts 8" low?

Or did you dial?

What's your dope at 200?

 

[bulldog87]

To get an 8 inch drop from 100 to 200 yards, your MV would have to be 2000 fps. And that's not 39.5 grains of 4350.

Checked on three different scales, it’s 39.5

 

[bulldog87]

Let me get this right.

Scope zeroed at 100, leaving turrets at 0 and holding the crosshairs on a bullseye at 200 gives impacts 8" low?

Or did you dial?

What's your dope at 200?

Exactly, did not dial, held dead on 100, 8 in drop at 200 yards. It makes zero sense, I’ve triple checked everything I know to check. But I’m only having this problem with the 143 gr bullet. So that’s what’s going over my head.

 

[2aBaC̶a̶]

Just spitballing here.

When is the last time you thoroughly cleaned it? May be starting a carbon ring.

It would really help you diagnose if you can run through a chrono.

Did you shoot other bullets after those, if so how did they shoot? Did you go back to the 100 to check zero?

Aside from a bullet issue something with the scope could have came loose.

 

[bulldog87]

Just spitballing here.

When is the last time you thoroughly cleaned it? May be starting a carbon ring.

It would really help you diagnose if you can run through a chrono.

Did you shoot other bullets after those, if so how did they shoot? Did you go back to the 100 to check zero?

Aside from a bullet issue something with the scope could have came loose.

After it began doing it, I cleaned everything. After the cleaning, I immediately backed up to 200. It shot the same drop, I then came into 150 (too much drop there as well), then to 100. Zero was good, just a 1/2 inch high at 100. I agree with the chrono, it needs to be done. One thing that I have not done, is let’s say load five of each the 120 and 143. And see what each shoots at 200, assuming that I figure out exact zero (100yds) for my 120 and adjust accordingly so it could be an accurate test. To see if there is any correlation at all. Would this be something worth doing?

 

[2aBaC̶a̶]

I would test using some factory ammo. It would tell you whether its the load or the gun.

It could just be a light load. Have you found what max is for your rifle?

When I load test I shoot some factory ammo that I know performs well before and after just to make sure the rifle is running good.

 

[Precision Underground]

Bullets don’t lie. If you are shooting anther load with the same rifle and not having the same issue the 143 has to be ridic slow. 39.5 is a light charge from my experience. Mine has ranged from 42 to almost 43 depending on the lot. Pretty sure the almost 43 lot had some moisture in it or something but it was very slow. If you don’t have a chrono the only solution is to load some higher charges and see where you get pressure. My guess is you will be able to work up to 3 more grains of powder without pressure.

 

[Bradv86]

Is there any chance that between different range sessions that you may have had a target hung at a different distance than you expected? I've seen ranges with many unmarked berms and I could imagine it would not be that difficult to be distracted and walk an extra 50yd. Other than anemic velocity I agree your issue sounds odd.

 

[bulldog87]

Is there any chance that between different range sessions that you may have had a target hung at a different distance than you expected? I've seen ranges with many unmarked berms and I could imagine it would not be that difficult to be distracted and walk an extra 50yd. Other than anemic velocity I agree your issue sounds odd.

Same range, it’s at my house every time. Thanks. It’s very odd

 

[Bradv86]

Gotcha. You never know. Factory Hornady 143 eld-x when zerod at 200 is listed as 7.9 inches drop at 300 so I figured I might throw it out there just in case as unlikely as it may be.

Lots of good suggestions here already so the cause will be found I'm sure soon enough. A good chrono will save a lot of heartache.

 

[308pirate]

@bulldog87 what's the muzzle velocity of these loads that have "excessive" drop at 200 yards?

You DO know what the velocities are, don't you?

If not, stop whatever you're doing until you buy a chrono. I can see reloading pistol cartridges for non-precision use without needing a chrono, but reloading rifle ammunition without the most direct measurement that correlates to chamber pressure (muzzle velocity) is just stupid.

 

[Tokay444]

So you’re dialing 1-1.2mil to hit accurately at 200 yards?

 

[bulldog87]

Update, issue is fixed. Thanks to everyone who helped. Charged the 4350 up to 42 and it made a massive difference. I also bumped my superperformance charges significantly for the 143gr and it performed well. I bumped up my 120 gmx to 47.1 and the gun started performing very very well, in fact its my best load so far. @2aBaCa I shot factory ammo first thing to make sure it wasn't the gun then bumped up the charge after that. @Precision Underground You called it with the 3 extra grains. I think this will lead to me ordering 120 eld m in the next few weeks.