New 153 gr A-tip Seating inconsistencies

creedmoor664

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Minuteman
Jun 10, 2019
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I was anxious to try some new Horn 153 gr A-tip so I broke down and bought a box of 100. I Measured them in sequence and all measured the same diameter and length with-in 1/2 of a thousand and base to ogive was .832 for all. I loaded them with H4350 at different weights for load development. I measured each loaded round to the ogive loading every 5 at different distances from the lands even though my bolt 6.5 RPR likes 0.010 to 0.015 as a sweet spot for now until I get my ordered new Bartlein gain twist barrel form SPR, hopefully in a few weeks. I noticed the first five (5) came out with depths varying by .001 to .003 measured from base to Ogive. I thought I had the variables all taken into consideration, but apparently not. Below is my method for reloading.


Here is my method for this batch of New Hornady 6.5 Creedmoor.:

New 6.5 Hornady Brass (all same lot)
Full case sized all to.288
Headspace compared cases at 5.554 all same size
Brass all same length overall
Primers all under flush.
all brass chamfered and reamed.
All 153 gr A-Tip bullets had the same base to Ogive exactly.
Used a Horn Match 544655 die with micro seater.
Hornady Iron Press with auto primer loader.

What else could I have done to get them within .001..... I used the same pressure seating them. I thought about putting a washer under the die thinking that might keep the pressure the same but wasn't any help. Any ideas?
 
I will add I ran them all through my Concentricity tool and made sure they were all within 1/2 thousand. I wasn't able to get a good closeup of a loaded round with ogive marks, not sure how that could help diagnose my problem?
 
I am putting only .002 pressure on loaded to sized cases. Less than that and they will slip in the case?

Neck tension is just one variable that affects seating pressure. What about the neck inner surface? Is is bare brass? Is there carbon fouling? Did you brush it? Did you use dry lube? Are the necks the same thickness? Hardness? Did you mix brass? It all matters.
 
Neck tension is just one variable that affects seating pressure. What about the neck inner surface? Is is bare brass? Is there carbon fouling? Did you brush it? Did you use dry lube? Are the necks the same thickness? Hardness? Did you mix brass? It all matters.


All those questions were answered in my original post.
New Brass, all same lot # and I did not Anneal any cases because they were new. I usually use Unique lube.
 
All those things 918v said will make a difference in seating depth. I used to get so frustrated with it but now I do a couple of extra things to prep the inside of the necks.

I use a Mandrel like many to open the necks separately from the the full size die (May also use Lee collet die). I don't use the expander ball. I wet tumble my cases so I use a spray graphite lube applied to the inside of the necks with a q-tip. It's kind of tedious but when I seat my bullets now they are almost always the same(+/-.001 or less). And I don't even sort bullets anymore. The more prep you put into the neck before makes a difference.

My other step I use is to use a RCBS plastic case brush chucked in a die grinder to polish/burnish the inside the necks also. I just run it in and out not getting crazy with it. That's just my process that works pretty good for me.
 
Last edited:
All those questions were answered in my original post.
New Brass, all same lot # and I did not Anneal any cases because they were new. I usually use Unique lube.

On the inside of the neck? I prefer Imperial graphite dry lube. When you say champhered and reamed, did you do that after sizing? Did you use a vld champher tool? Because a standard champher tool leaves a small burr on the inside diameter of the cut and this causes a sort of speed bump during seating. A vld tool is much better.
 
On the inside of the neck? I prefer Imperial graphite dry lube. When you say champhered and reamed, did you do that after sizing? Did you use a vld champher tool? Because a standard champher tool leaves a small burr on the inside diameter of the cut and this causes a sort of speed bump during seating. A vld tool is much better.
I see the
On the inside of the neck? I prefer Imperial graphite dry lube. When you say champhered and reamed, did you do that after sizing? Did you use a vld champher tool? Because a standard champher tool leaves a small burr on the inside diameter of the cut and this causes a sort of speed bump during seating. A vld tool is much better.

That makes sense. I will examine the rest of my prepped cases and will get a VLD tool. Thanks, Ken
Will +/-.0015 effect
Will +/-.0015 effect your accuracy?

Probably not, but who doesn't want to shoot as absolutely good as they can. I always try to eliminate as many reasons as I can that prevent me from not doing my best. Just my humble opinion....
 
CM664,
Sounds like being anal about precision in reloading makes you happy.
Good for you.

I do the same. :)
I have a F-Class match Saturday.
I sorted out 70 88EMD-M's, 70 Dogtown once fired 22N cases, and charged with 10.495-10.500 carats of Staball 6.5 at 2.465". Then checked cartridge weight to make sure I didn't make a mistake. Cartridge weight came out to 233.0 to 233.2 grains. Had one @233.4 :( Put it in the sighters row.
This is a new powder new load for me. Only got to try it @ 100. I'm also loading up 70 of my old standby load just in case.
 
I have the Hornady Match dies with the VLD stem for my 300PRC using a RCBS Summit and it does not have any consistency what so ever with seating depth. I’ve never had this much issue with seating depth before.
I mention that in case it’s your die
 
CM664,
Sounds like being anal about precision in reloading makes you happy.
Good for you.

I do the same. :)
I have a F-Class match Saturday.
I sorted out 70 88EMD-M's, 70 Dogtown once fired 22N cases, and charged with 10.495-10.500 carats of Staball 6.5 at 2.465". Then checked cartridge weight to make sure I didn't make a mistake. Cartridge weight came out to 233.0 to 233.2 grains. Had one @233.4 :( Put it in the sighters row.
This is a new powder new load for me. Only got to try it @ 100. I'm also loading up 70 of my old standby load just in case.

Now that's what I'm talkin about, eliminate the negative accentuate the positive
 
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cm664,
I pick dies for function even if the brands don't match.
The Hornady Full length die usually takes less force to pull the expander out than Redding or RCBS.
but for most calibers I use a Redding body die instead.
It makes for more steps but I get pretty consistent bumps with it.
For neck sizing I use the Lee collet die. You can feel the die pushing the brass.
Lee will make a custom collet but I modified a .223 one for my 22 Nosler.
They also sell undersized mandrels.
To seat bullets the Hornady with a polished stem seems to really work well for me.
I had to do a little shaping to the stem as most High BC bullets are delicate where the stem contacts the ogive. Haven't tried the A-tip yet but the ELD's will slightly distort with pressure over the hollow part.
Pushing an ogive shape it doesn't take much compression to make a bigger difference in length than say a flat nose bullet.
A hard to seat bullet might end up long due to taking up slack in the press but a very small amount of marking/denting of the ojive will also make it long by not pushing as far.
I also seat very very slowly. More force is needed when run into the case fast.
Powdered Mica seems to help.
 
cm664,
I pick dies for function even if the brands don't match.
The Hornady Full length die usually takes less force to pull the expander out than Redding or RCBS.
but for most calibers I use a Redding body die instead.
It makes for more steps but I get pretty consistent bumps with it.
For neck sizing I use the Lee collet die. You can feel the die pushing the brass.
Lee will make a custom collet but I modified a .223 one for my 22 Nosler.
They also sell undersized mandrels.
To seat bullets the Hornady with a polished stem seems to really work well for me.
I had to do a little shaping to the stem as most High BC bullets are delicate where the stem contacts the ogive. Haven't tried the A-tip yet but the ELD's will slightly distort with pressure over the hollow part.
Pushing an ogive shape it doesn't take much compression to make a bigger difference in length than say a flat nose bullet.
A hard to seat bullet might end up long due to taking up slack in the press but a very small amount of marking/denting of the ojive will also make it long by not pushing as far.
I also seat very very slowly. More force is needed when run into the case fast.
Powdered Mica seems to help.
Have you ever used Forester Products?
Their Bench rest stuff is second to none.
Their bushing bump neck sizing dies are another customizable option.

This set here is a well rounded product.
 
cm664,
I pick dies for function even if the brands don't match.
The Hornady Full length die usually takes less force to pull the expander out than Redding or RCBS.
but for most calibers I use a Redding body die instead.
It makes for more steps but I get pretty consistent bumps with it.
For neck sizing I use the Lee collet die. You can feel the die pushing the brass.
Lee will make a custom collet but I modified a .223 one for my 22 Nosler.
They also sell undersized mandrels.
To seat bullets the Hornady with a polished stem seems to really work well for me.
I had to do a little shaping to the stem as most High BC bullets are delicate where the stem contacts the ogive. Haven't tried the A-tip yet but the ELD's will slightly distort with pressure over the hollow part.
Pushing an ogive shape it doesn't take much compression to make a bigger difference in length than say a flat nose bullet.
A hard to seat bullet might end up long due to taking up slack in the press but a very small amount of marking/denting of the ojive will also make it long by not pushing as far.
I also seat very very slowly. More force is needed when run into the case fast.
Powdered Mica seems to help.


With the new Hornady a tip both 135 and 153 grain you'll need a seating stem specifically for them. They are very long bullets and much longer than the ELD match that I've been using for years. I am not necessarily A propriety driven reloader because one brand doesn't always suit my needs, but for the 6.5 Creedmoor I like the Hornady match die set. Just my preference
Have you ever used Forester Products?
Their Bench rest stuff is second to none.
Their bushing bump neck sizing dies are another customizable option.

This set here is a well rounded product.
 
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This is why I like using pin gauges to spot check and hydropress to seat.

I can set up my my process to set the desired neck tension and verify with pin gauge. Then while seating on a hydro, I know instantly if something didn’t seat the same as the rest.

Also, hornady offers seating stems specifically for the A-Tips. Not sure if that makes a huge difference or not. But hornady seems to think so.
 
Also, as mentioned above, seating pressure and neck tension are not always inline with one another.

You can have two cases set with .002 neck tension. And they each may have different seating pressure. This is a friction issue. It’s harder to measure without an arbor press.

Solution is to lube/graphite/moly necks if friction is an issue.
 
Update:
After listening to everyone's replies, I decided to try a few new things. First I took a batch of same lot # once-fired cleaned Hornady brass, sized and chamfered them at a much less angle than I had been using, but producing a visible angle on the cases. I also made sure the interior of the neck was buffed with a good medium brush and thirdly I dipped the A-Tip 153 gr bullets in ultrafine graphite powder and then seated 10 rounds at .015 of the lands on my rifle. All rounds came out within .001 when seated and 7 were right on. It seems my prep needed tweaking a little more. It's great not to have to sneak up on rounds just to get consistency. Thanks , Sniper Hide Gang. ......
 
I was anxious to try some new Horn 153 gr A-tip so I broke down and bought a box of 100. I Measured them in sequence and all measured the same diameter and length with-in 1/2 of a thousand and base to ogive was .832 for all. I loaded them with H4350 at different weights for load development. I measured each loaded round to the ogive loading every 5 at different distances from the lands even though my bolt 6.5 RPR likes 0.010 to 0.015 as a sweet spot for now until I get my ordered new Bartlein gain twist barrel form SPR, hopefully in a few weeks. I noticed the first five (5) came out with depths varying by .001 to .003 measured from base to Ogive. I thought I had the variables all taken into consideration, but apparently not. Below is my method for reloading.


Here is my method for this batch of New Hornady 6.5 Creedmoor.:

New 6.5 Hornady Brass (all same lot)
Full case sized all to.288
Headspace compared cases at 5.554 all same size
Brass all same length overall
Primers all under flush.
all brass chamfered and reamed.
All 153 gr A-Tip bullets had the same base to Ogive exactly.
Used a Horn Match 544655 die with micro seater.
Hornady Iron Press with auto primer loader.

What else could I have done to get them within .001..... I used the same pressure seating them. I thought about putting a washer under the die thinking that might keep the pressure the same but wasn't any help. Any ideas?
When you were seating the bullet, did you notice a variation in the pressure between bullets?
With new brass, there will always be an inconsistency in the neck, which might be your source. Also I do a double pump when seating the bullet. Both pumps are to the stop. The first pump seats the bullet and when released the neck tension may push it out slightly. The second pump overcomes that neck tension push and results in a consistent result.