110 6mm A-Tip in a 6x47 Lapua

[dstoenner]

One of the gifts I asked for Christmas was a box of A-Tips to try out in my 6X47 Lapua. I went to evaluate these new bullets and came up with some surprises. Looking to see what others might have found out for the caliber they are interested in.

Like I do with all of my bullets I take 3 measurements - OAL, base to Ogive and Tip to Ogive of boat tail. I then plug them into my spreadsheet that gives me a range of loaded lengths. The minimum length is based on not letting the ogive go into the case neck. The maximum is based on keeping 1 caliber length of bearing surface in the neck. So the min is 2.453 and the max is 2.732. Next was to measure the length in my chamber to the lands. That was where I got the surprise.

My current barrel has 1944 rounds on it. From a new barrel to now the throat has advanced about .060 on average. My match bullet is either a Berger 105 Hybrid or 115 DTAC. In both cases I have not reached max so I am chasing the lands. And it looks like I will go to the end of the barrel without having to stop chasing the lands if I can get 2500 to 3000 rounds out of this barrel.

BUT the 110 A-Tip measured 2.795 WHAT!!! I measured again and got the same answer within a couple of thousands. I have a new barrel that I just got through breaking in and it has ~250 rounds, so I measured it and came up with 2.735.

I normally start any load development at .020 jump so I am never in danger of pulling a bullet if the line goes cold. No matter how you cut it this bullet will have to jump a whole bunch. My throat for the initial chamber is .104 which I think is sort of middle of the road in length. I would have to go to 0 throat in order to be able to chase the lands to the end of barrel life. I am not for sure what Hornady was thinking when they designed this bullet but for me it seems to be a non starter.

What are any of you guys finding with this bullet in your chambers?

David

 

[johara1]

I really don't understand your measuring, I check for uniformity. Anyway I start in to a square mark on the lands, then back out .002 at a time till it shoots. then adjust the powder from there..... They seem to like to be in a little ...... jim

 

[DaveTooley]

Yes it has a long ogive length like any VLD style bullet. Add in the the extra length the tip adds vs. a BT and you have your answer.

 

[dmoran]

.... The maximum is based on keeping 1 caliber length of bearing surface in the neck....

That rule of thumb (I'll call it) has no merit in my opinion.
Many light bullets don't even have that much bearing/shank length for one reason.
Myself have ran with as little as .050" of bearing/shank seated in the neck, yielding benchrest accuracy.
And there are cartridges that don't even have a caliber length of neck (example below)
All the same, good luck with your endeavors with the 110 A-Tip!.!.!

 

[johara1]

I don't care about the dimensions of a bullet, but more on on how it shoots. In a few moves it was shooting in the the low zeros at 100 yds ES was a single digits and with the uniformity of the bullet and the high BC. it will hammer. I had did my testing with a 6br imp. @2920. The 6x47 my leave a little to be desired..... jim

 

[dstoenner]

Well as they say the plot thickens. After the few responses, I thought I would see what my 6BR measures. Should come as no surprise because my 6BR has a throat of .110 as best I could measure. This barrel has about 400 rounds through it and it measures 2.460 which is right to my max length with no ability to chase the lands as is the case with the 6x47.

Donovan,

I have seen that benchrest cartridge before and I scratched my head then. My own experiments using my Redding Competition seater and seating bullets without much bearing surface was that the resulted load round had poorer runout than if it was seated a little deeper in the same piece of brass. Each .010 deeper the runout was slightly less till I hit close to the caliber of bearing surface in the neck. I never jam anything but I can see where jamming a bullet with very little bearing surface could result in good runout and good accuracy. Just not my luxury here.

To all,

I am going to load 10 up with Lapua brass/H4350/450 and see what I get on target with them. Probably do the same with my BR. I got them to see. You can't tell till you give them a chance.

David

 

[johara1]

Well as they say the plot thickens. After the few responses, I thought I would see what my 6BR measures. Should come as no surprise because my 6BR has a throat of .110 as best I could measure. This barrel has about 400 rounds through it and it measures 2.460 which is right to my max length with no ability to chase the lands as is the case with the 6x47.

Donovan,

I have seen that benchrest cartridge before and I scratched my head then. My own experiments using my Redding Competition seater and seating bullets without much bearing surface was that the resulted load round had poorer runout than if it was seated a little deeper in the same piece of brass. Each .010 deeper the runout was slightly less till I hit close to the caliber of bearing surface in the neck. I never jam anything but I can see where jamming a bullet with very little bearing surface could result in good runout and good accuracy. Just not my luxury here.

To all,

I am going to load 10 up with Lapua brass/H4350/450 and see what I get on target with them. Probably do the same with my BR. I got them to see. You can't tell till you give them a chance.

David

I'm using a .135 free bore and I had no issues starting in to a square mark. and backing out at .002 at a time and never pulled a bullet on anything except a Spencer 103 that were .005 fat at the pressure ring. I am using a 7 twist barrel with .001 neck tension.... jim

 

[dmoran]

I have seen that benchrest cartridge before and I scratched my head then. My own experiments using my Redding Competition seater and seating bullets without much bearing surface was that the resulted load round had poorer runout than if it was seated a little deeper in the same piece of brass. Each .010 deeper the runout was slightly less till I hit close to the caliber of bearing surface in the neck. I never jam anything but I can see where jamming a bullet with very little bearing surface could result in good runout and good accuracy. Just not my luxury here.

Inline seating dies (Wilson, Sinclair, etc..) would likely resolve much of your runout issues.
Never seen a threaded press seating die yet that can better the concentricity of inline seating dies.

 

[dstoenner]

Inline seating dies (Wilson, Sinclair, etc..) would likely resolve much of your runout issues.
Never seen a threaded press seating die yet that can better the concentricity of inline seating dies.

I have inline seaters for my 6BR and 6x47L. I bought them on the chance that I might do load development at the range. So I ran a test and loaded 25 cases out of a lot same bullet same length on my Redding Competition seater and another 25 out of the same lot, same load with the inline seater. I then measured runout I got 12 .001 with the Redding and 13 .001 with the Wilson. The rest were .002 with each one producing a single .003. German Salazar did the same experiment and then shot the loaded rounds at distance. He compared like 5 seaters. Redding and Wilson were virtually tied in first place, then there was a bug space to the rest of the group. The targets showed exactly the same thing.

I have to admit I have not tried a seat of only say .050 in the case on both if these. Mine were seated my earlier statement of at least 1 caliber in the neck.

I don't feel like I have runout issues when my load density typically runs 50-60% .001 with another 20% or more .002 out of batches of 90 - 95 cases. I can't ask for any better. I do not anneal my Lapua brass which might be a bigger help than which seater I use. My goal is to get the best bang for the buck. I can buy a lot of brass for $1K for an AMP annealer.

David

 

[dmoran]

@dstoenner
Was replying to your statement: "Each .010 deeper the runout was slightly less till I hit close to the caliber of bearing surface in the neck" and to why you justify the need of a caliber length of bearing/shank seated. Can totally believe you will have runout issues using conventional threaded press dies for "shallow" seating, and why I suggested inline dies instead (not sure of the relevance in your last reply).

 

[dstoenner]

@dstoenner
Was replying to your statement: "Each .010 deeper the runout was slightly less till I hit close to the caliber of bearing surface in the neck" and to why you justify the need of a caliber length of bearing/shank seated. Can totally believe you will have runout issues using conventional threaded press dies for "shallow" seating, and why I suggested inline dies instead (not sure of the relevance in your last reply).

I thought you were saying that threaded dies have runout issues regardless. Without trying this statement out, I will have to assume you are right. When I get a chance I will run a comparison test to find out for myself. Maybe these wilson dies might come in handier than I thought.

David

 

[Zero333]

If you're single feeding, like dmoran stated, it doesn't matter how little bullet shank you have inside the neck.

As long as the bullet doesn't fall out when you pick up the cartridge and go to load it.

 

[Joel Dubose]

This is an interesting topic. I shoot a 6mm CM and have tested many different bullets in it. All of what your saying became very relevant when I wanted to test the 110 smk. It has an even longer nose radius than the 110 Atip. Leaving very little of the bullet in the neck as well. I started looking at the difference between what Berger was saying about the VLD and the Hybread 105. Initially Berger was saying that the VLD needed to be right at the lands, however accuracy wasn't what they wanted it to be. Berger then started looking at what the hunters where doing that was showing better accuracy and then recommended jumping the bullet a lot farther. I believe that they set up testing parameters in .010 increments or even greater. Starting off about .005 off the lands and moving into and away from the lands. Most of the people that I know that has tested this, (that will speak with me) said that they found that it liked a .070 jump or more. Me personally dont like the idea of not having much brg surface pressed into the neck. Run out isn't my concern it's more about how the Bullet would opturate to the bore. I think that David Tubbs might have been spot on with the design of his 115 DTAC and purposes of the rebates boat tail. It will be interesting to follow this thread if you guys will share your results from testing. That would be a very good thing.

 

[dstoenner]

@Joel Dubose
I found exactly the same thing that you did with the SMK 110. I am not for sure what these companies are thinking. Right now I am using them up in my 6BR because it shoots every bullet I feed it well, even on the second barrel. I don't shoot Berger VLDs after they came out with the Hybrid design. It is like a lot of SMK's, it seems very jump tolerant.

When I went to the 6x47Lapua for my F-Class cartridge, I had thought that I would be using the 105 Hybrid running at 3050 to 3100 would shoot inside my 260 Remington running 140 hybrids. But when I rebarreled from the 260 to the 6x47 and did load development all I could do was 2990 as a node with H4350. So I looked hard at the 115 DTAC and found it to be everything I was wanting. My load for the 115 I get 2950 which shots inside my 260 and I can chase the lands. Tonight I had been to the range for position practice with my rifle and that put me right at 2K rounds so I measured the throat for my records. I can still load the 115 out to 2.737 keeping 1 caliber of bearing surface in the neck and jump .020 which has been this bullets sweet spot. But I think this barrel will be gone at 2500 rounds. They are consumables, right

I am going to load up about 20 rounds of A-Tips, 10 at max length of 2.732 which keeps 1 caliber in the neck and then 10 at whatever gives my only a .020 jump and give them a try. When I get that done, I will share my results.

Thank you for speaking up, that somebody else shares my point of view.

David

 

[dstoenner]

If you're single feeding, like dmoran stated, it doesn't matter how little bullet shank you have inside the neck.

As long as the bullet doesn't fall out when you pick up the cartridge and go to load it.

So I have loaded up 40 rounds to test. I have a group of 40 Lapua cases that I use for testing. I sorted these cases unloaded for neck runout. 39 were .001 or less and 1 was .002. So good brass was going into each seater. The one that was .002 runout came out loaded at .001!!

I loaded 10 110 A-Tip using my Redding Competition seater at 2.735, 10 110 A-Tip at 2.845 (.020 off my current lands) with the Wilson Micrometer seater and 20 of my 115 DTAC match load at 2.700 with the Wilson Micrometer seater. This was to test what you were saying about the Wilson being better than a Redding Competition seater.

I then rolled each batch individually to see what concentricity is

Batch 1 with Redding Competition seater

5 at .001
5 at .002

Batch 2 with Wilson Micrometer seater

6 at .001
1 at .002
4 at .003

Batch 3 with Wilson Micrometer seater

6 at .001
3 at .002
11 at .003

Maybe I don't know how to milk all .001 runout with the Wilson. My personal experience is that .002 or less is fine even at 1000. Shoots well inside my wind calls for sure. I have shot some .003 at 1000 and never had what I call a flier. But my normal loading with the Redding out of a single batch of 92 grouped cases is that I will get 40 to 45 .001, 26 to 30 .002 and the rest .003 with maybe 1 .004.

What bothers me is that in both groups with the Wilson is that I had 2 nodes of 1 and 3. Not sure what is going on. Both seaters have VLD stems inserted in them. I verified that the seater stem was leaving a slight mark on the nose of the bullet, down form either the tip or meplet. Any thoughts? This is the second time I have tried this test and came up with the basic same results. The Redding does a better job.

David

 

[Zero333]

So I have loaded up 40 rounds to test. I have a group of 40 Lapua cases that I use for testing. I sorted these cases unloaded for neck runout. 39 were .001 or less and 1 was .002. So good brass was going into each seater. The one that was .002 runout came out loaded at .001!!

I loaded 10 110 A-Tip using my Redding Competition seater at 2.735, 10 110 A-Tip at 2.845 (.020 off my current lands) with the Wilson Micrometer seater and 20 of my 115 DTAC match load at 2.700 with the Wilson Micrometer seater. This was to test what you were saying about the Wilson being better than a Redding Competition seater.

I then rolled each batch individually to see what concentricity is

Batch 1 with Redding Competition seater

5 at .001
5 at .002

Batch 2 with Wilson Micrometer seater

6 at .001
1 at .002
4 at .003

Batch 3 with Wilson Micrometer seater

6 at .001
3 at .002
11 at .003

Maybe I don't know how to milk all .001 runout with the Wilson. My personal experience is that .002 or less is fine even at 1000. Shoots well inside my wind calls for sure. I have shot some .003 at 1000 and never had what I call a flier. But my normal loading with the Redding out of a single batch of 92 grouped cases is that I will get 40 to 45 .001, 26 to 30 .002 and the rest .003 with maybe 1 .004.

What bothers me is that in both groups with the Wilson is that I had 2 nodes of 1 and 3. Not sure what is going on. Both seaters have VLD stems inserted in them. I verified that the seater stem was leaving a slight mark on the nose of the bullet, down form either the tip or meplet. Any thoughts? This is the second time I have tried this test and came up with the basic same results. The Redding does a better job.

David

As long as they're all less than 4 thou run out. As you saw, the target didn't care.

 

[Uncle Mike]

@Joel Dubose
I found exactly the same thing that you did with the SMK 110. I am not for sure what these companies are thinking. Right now I am using them up in my 6BR because it shoots every bullet I feed it well, even on the second barrel. I don't shoot Berger VLDs after they came out with the Hybrid design. It is like a lot of SMK's, it seems very jump tolerant.

When I went to the 6x47Lapua for my F-Class cartridge, I had thought that I would be using the 105 Hybrid running at 3050 to 3100 would shoot inside my 260 Remington running 140 hybrids. But when I rebarreled from the 260 to the 6x47 and did load development all I could do was 2990 as a node with H4350. So I looked hard at the 115 DTAC and found it to be everything I was wanting. My load for the 115 I get 2950 which shots inside my 260 and I can chase the lands. Tonight I had been to the range for position practice with my rifle and that put me right at 2K rounds so I measured the throat for my records. I can still load the 115 out to 2.737 keeping 1 caliber of bearing surface in the neck and jump .020 which has been this bullets sweet spot. But I think this barrel will be gone at 2500 rounds. They are consumables, right

I am going to load up about 20 rounds of A-Tips, 10 at max length of 2.732 which keeps 1 caliber in the neck and then 10 at whatever gives my only a .020 jump and give them a try. When I get that done, I will share my results.

Thank you for speaking up, that somebody else shares my point of view.

David

What is your twist to stabilize 115?

 

[dstoenner]

What is your twist to stabilize 115?

I am running a 1:7 McGowen. I have heard of people reporting that even a 1:8 works with 115 DTAC. I am skeptical but...

David

 

[Ranger188]

I had really good luck running a 7.5 tw with the 115 dtac's and 110's