Primer Puncture

[survivalshop]

Is your Bolt , one of those High Pressure Bolts with the smaller Firing Pin dia. ?

[98Z5V]

8 hours ago, Phantom30 said:

You, are a complete lost cause. 

Good luck with your hot loads, and BCA barrels.  I don't think you're smart enough to figure it out.

Maybe you should open your eyes a little, and learn something.  Start here:

http://americanshootingjournal.com/260-remington-vs-6-5-creedmoor/

Edited July 26, 2019 by 98Z5V

[Phantom30]

Nice article:  "At the end of the day, it really depends on personal preference".  No Science there.

I am talking about a mechanical phenomenon where tips are being dented because of the nature of the Creedmoor round design and its relationship to a barrel extension which was designed for another caliber.  The table in the SAAMI comparison shows that the 260 Max COAL bullet exposure from the neck is Shorter than the 6.5 Min COAL exposure.  There is a lot more 6.5 sticking out before the casing hits anything than with the 260.  This also is true of the 6mm.

 

Survival shop:  The BCG is a NiB Tool Kraft don't know if that means a non-standard firing pin or not.  In my original write up there were pin measuremenst but no diameters so I'll have to check it.

[98Z5V]

3 hours ago, Phantom30 said:

Nice article:  "At the end of the day, it really depends on personal preference".  No Science there.

I am talking about a mechanical phenomenon where tips are being dented because of the nature of the Creedmoor round design and its relationship to a barrel extension which was designed for another caliber.  The table in the SAAMI comparison shows that the 260 Max COAL bullet exposure from the neck is Shorter than the 6.5 Min COAL exposure.  There is a lot more 6.5 sticking out before the casing hits anything than with the 260.  This also is true of the 6mm.

There IS science there, you just refuse to accept that.  You refute anything that's said to you about reloading, hot loads, all of that - because someone that's shooting 6.5 Creedmoor hasn't chimed in yet. 

I gave you that article to inform you - INFORM YOU.  There are alot more similarities between .260 Rem and 6.5 CM than you're willing to open your mind to. You're just too blind in your thinking that you think I don't know what I'm talking about, when comparing my downrange accuracy results, to your hypothetical suppositions on bullet tips.  I've done it.  Repeatedly.  You "think" it...  I'm telling you that you're wrong, if all these bullet tips on Hornady ELD-M MUST dent or deform upon chambering, like you state that they do.  I'm not seeing it, downrange, at 850 yards.  Not at all.

However, you stick to this "dented tip" is affecting impact at 1000 yards - yet you have zero experience with 1000 yards.  You stated your experience, and it's all short range.

You state these bullets WILL have tip impact when chambering - my Wilson Combat .260 Rem barrel doesn't mess up the tips on my Hornady ELD-M projectiles that I handload.  Maybe you need to look at your hot loads, first, for your pierced primers, and back it down.  Maybe you need to look at your budget Bear Creek Arsenal barrels, and see what's going on there, on your projectile tip damage.

You can put up as many fancy graphs and charts that you want - you'll only show, what you don't know.  As I explained before, with your lack of ANY crimp, and chambering a round from the locked back position, by using the bolt release...  WTF did you think would happen?   Oh, yeah - you just didn't even know that what you did was a stupid test.  However, many charts, pics, and info came out from that...

That's just what you do...  Inundate with BS information, hoping that someone thinks it's cool - and believes you... 

Edited July 26, 2019 by 98Z5V

[98Z5V]

@Phantom30, so answer this one...  Why am I not having issues with my stuff at 850 yards?...   Why is that?...

[survivalshop]

Looks like it has the smaller HP FP Bolt design . The 6.5 CM in Ar's has always had a Primer puncturing issue & is why some use small Primer pocket  Brass & small Primers for reloading ,also for longer Brass  service life.The HP Bolt helps but not with all loadings .

 

Toolcraft 6.5 Creedmoor Bolt Carrier Group

Made in the U.S.A – Lifetime Warranty

The Toolcraft 6.5 Creedmoor Bolt Carrier Group in black nitride is a Full Auto BCG, manufactured using a 9310 steel bolt and a 8620 steel carrier.  Features forward assist serrations and is fully DPMS compatible.  The Toolcraft 6.5 Creedmoor Bolt Carrier Group is 100% compatible with the higher pressure 6.5 Creedmoor cartridge.

Toolcraft is an OEM for the U.S. military and many other large rifle manufacturers, producing the most popular, and well built AR10 bolt carrier group on the market.  Forget the fancy logo at a $75 premium, and buy direct from Arm or Ally, the internet’s largest dealer of Toolcraft products.  All of our Toolcraft Bolt Carrier Groups come with a 100% hassle free Lifetime Warranty – should any Toolcraft product fail, simply contact us for replacement.  We are proud to feature Toolcraft products along with our already fantastic line-up of reputable manufacturers.

We also offer a Toolcraft 6.5 Creedmoor Double Ejector BCGfeaturing a 0.065″ reduced diameter firing pin and firing pin channel.  Historically, the large format AR10 variants are known to have ejection problems. The addition of the second ejector ensures consistent ejection and greatly improves reliability of your AR10 rifle.

Edited July 26, 2019 by survivalshop

[Phantom30]

Well lets try this in reverse order.  You are shooting 260 Remington not Creedmoor in 6.5 or 6mm.  The differences in the from of the rounds are much different as shown in the SAAMI data. 

My short range experience applies to the experiments with tip deformation, meaning I have not tried to examine the effects at long ranges.  Why, because if it shows up at short range it only stands to reason that it will be worse at longer ranges.  The context for short range had nothing to do with overall experience, only the data at hand.

Phantom30 is one of my combat call signs

Yes BCA barrels are cheap, and you are correct in that relationship between the Creedmoor caliber and the barrel extension is one of the factors I am concerned about.  But that would apply to most any barrel using those design components.

Crimp, yes strong crimp is necessary for auto feeder ammo, I have hand loaded nothing in this discussion other then the few dummy rounds.  Wasn't concern much about the retention, just wanted to be able to slam ELD into the breech and recover them to examine the tip effects.  Using bolt hold back force is just a way to get it fed.  All the rounds used in the examination were factory rounds,   Their were more than eight different brands or types.

Yes SP type bullets are not recommended for AR class rifles.  Why because you screw the tips up when you chamber them, i.e. Hornady White Tail.  So I confirmed the obvious.  But that's what you do to establish a baseline case.

Hot loads in this case would have to be a factory error, since the S&B 140gr FMJ rounds are all factory loads.  In a PRS evaluation of Creedmoor rounds the S&B round standard deviation on muzzle velocity was measured under ten feet per second.  If you want I can look up the article for you.  They remarked how consistent they where compared to the other factory loads.  They also remarked that other factors involved made them not as accurate as some other brands used in their test, but they didn't specify the factors that caused it.

Now my Primer punch,  Yes it is four punches out of eight rounds all from the same box.  Lot data not confirmed, but was assumed on my part to be all the same since they were all purchased in a single 500 round case.  My bad as I said before I'll have to confirm the lots, from the few boxes that are left. 

 

 

 

[Phantom30]

Survival shop:  Great thanks.  I'll have to measure the pin this morning.  I now have a large pile of large primer brass to work with so buying the small primer cases is great for the future, but is there a recommended tougher primer that will work in the S&B brass?  Toolcraft stuff appears quality.  Had a KAK double ejector bolt and it was a miserable fit in the AP receivers, so I replaced it with a Davidson bolt.   

[Phantom30]

Ammo Lots Two Cases: 25 boxes of 20  Lot marked 11/22  and 16/78 

Cases were divided with a friend, reduces my count to 12 boxes per case

Purchased from BX lot 16/78 (2 Boxes)

Purchased from store Lot 11/10 (5 Boxes)

 

20 round Boxes containing fired casing retained for reloading

By Lot number inside lid:

16/82 2 boxes, 11/22 11 Boxes, 11/10 3 boxes, 16/78  3 boxes

Hot Box is an another 16/78, half box remaining live

Boxes remaining live rounds

16/78 4 Boxes, 11/10 2 Boxes

4 boxes of assumed lot 16/78 have been fired but evidence not retained

1 Box of assumed lot 11/12 have been fired but evidence not retained

 

 Survival Shop:  Accessible Firing Pin diameter measurements for comparison, HP FP?

 

Toolcraft NiB firing Pin  tip shaft 0.077” dia.   Second step 0.103” dia.,  Third step 0.153” dia.

KAK Double Ejector Pin  tip shaft 0.078” dia.   Second step 0.103” dia.,  Third step 0.154” dia.

JAPO coated BCG Pin  tip shaft 0.079” dia.   Second step 0.103” dia.,  Third step 0.154” dia.

 

[survivalshop]

3 hours ago, Phantom30 said:

Ammo Lots Two Cases: 25 boxes of 20  Lot marked 11/22  and 16/78 

Cases were divided with a friend, reduces my count to 12 boxes per case

Purchased from BX lot 16/78 (2 Boxes)

Purchased from store Lot 11/10 (5 Boxes)

 

20 round Boxes containing fired casing retained for reloading

By Lot number inside lid:

16/82 2 boxes, 11/22 11 Boxes, 11/10 3 boxes, 16/78  3 boxes

Hot Box is an another 16/78, half box remaining live

Boxes remaining live rounds

16/78 4 Boxes, 11/10 2 Boxes

4 boxes of assumed lot 16/78 have been fired but evidence not retained

1 Box of assumed lot 11/12 have been fired but evidence not retained

 

 Survival Shop:  Accessible Firing Pin diameter measurements for comparison, HP FP?

 

Toolcraft NiB firing Pin  tip shaft 0.077” dia.   Second step 0.103” dia.,  Third step 0.153” dia.

KAK Double Ejector Pin  tip shaft 0.078” dia.   Second step 0.103” dia.,  Third step 0.154” dia.

JAPO coated BCG Pin  tip shaft 0.079” dia.   Second step 0.103” dia.,  Third step 0.154” dia.

 

What did you use to measure the FP ? Micrometer ? or a Dial/Digital Caliper's ?

They list both  HP & STD Bolts on their sight , I don't have a TC BCG so I can't check FP size . Makes me wonder which you have .

Edited July 26, 2019 by survivalshop

[Phantom30]

Fowler Analog Caliper

[98Z5V]

14 hours ago, Phantom30 said:

Hot loads in this case would have to be a factory error, since the S&B 140gr FMJ rounds are all factory loads.  In a PRS evaluation of Creedmoor rounds the S&B round standard deviation on muzzle velocity was measured under ten feet per second.  If you want I can look up the article for you.

I said that in the very first response you got in this thread! 

You don't need to look up any articles for me - If you post chrono data, I want it to be YOUR chrono data that YOU shot...  

14 hours ago, Phantom30 said:

 Had a KAK double ejector bolt and it was a miserable fit in the AP receivers, so I replaced it with a Davidson bolt.   

Would that be Davidson Defense, by chance?...

[Cliff R]

Just curious.  What do the primers look like in the fired cases that don't puncture?  Are they showing you signs of high pressure, heavy "crater" and material rolling back over the firing pin to a point where it's raised up or you can catch it with your fingernail?

Factory loads or not the rule of thumb should always be to stop shooting any ammo that gives you troubles until you find the culprit. 

I'd start be looking very closely at all the fired cases.

Then I'd yank a few bullets and measure the powder charge, mic a few of the bullets, check overall length, etc.

Factory ammo is typically loaded to be well within standards for pressure, but keep in mind you are dealing with a "high performance" cartridge, and it's in an auto-loading platform.  It's also a damned long bullet so has considerable resistance or "drag" in the barrel which can cause a pretty rapid pressure rise in some weapons.  So it changes the game a bit as there is a lot more going in the AR than just closing the bolt, firing a round, then ejecting the spent your manually.

In any and all cases, what I would do here, just like I did way back in the mid 1980's when we got our first batch of M-9 pistols and started having issues with them.  We STOPPED firing them until we figured out the problem.  The problem in that case was the ammunition.  I noticed that on night fire sessions or even late in the evening the TZZ ammo produced a HUGE fireball, much larger than the Winchester/Olin ammo we had available.  It also came in 64 round boxes, not 50 rounds.  I suspected at that time that it was loaded for UZI's as they have 32 round magazines.  In any case we stopped shooting the Israeli Industries TZZ 9mm ammo. 

Sure enough it was a good call on my part as very soon after a couple guns malfunctioned on other ranges with minor injuries to the shooters.  The rest of that story is history, some may remember it, some may not, depends on when you served and what your job description was........Cliff

Edited July 27, 2019 by Cliff R

[98Z5V]

10 hours ago, Cliff R said:

Sure enough it was a good call on my part as very soon after a couple guns malfunctioned on other ranges with minor injuries to the shooters.  The rest of that story is history, some may remember it, some may not, depends on when you served and what your job description was........Cliff

Yep. Beretta M9 slides started coming apart...  

[survivalshop]

It could very well be the batch of Ammo , but it also may not be , I believe if it was Ammo , it would also show signs of over pressure in other platforms , maybe not the same , but you would still notice something. I would like to see this same batch or box of ammo's spent Brass that was shot from another Rifle . One other thing that may need to be looked at , the Firing Pin Hole in the Face of the Bolt

. One of reasons for using Small Primer Pockets , less area ( Dia ) makes for a stronger Primer , less likely to flow in around the Fining Pin , allowing less chance of rupture with High Performance Loadings . Same goes for the HP Bolt / small dia.Firing Pin .

[98Z5V]

2 minutes ago, survivalshop said:

It could very well be the batch of Ammo , but it also may not be , I believe if it was Ammo , it would also show signs of over pressure in other platforms , maybe not the same , but you would still notice something. I would like to see this same batch or box of ammo's spent Brass that was shot from another Rifle . One other thing that may need to be looked at , the Firing Pin Hole in the Face of the Bolt

. One of reasons for using Small Primer Pockets , less area ( Dia ) makes for a stronger Primer , less likely to flow in around the Fining Pin , allowing less chance of rupture with High Performance Loadings . Same goes for the HP Bolt / small dia.Firing Pin .

He claims he's got 700-800 rounds of the same ammo through his gun, no issues until the last 4 out of 8 (can't remember his later posts now, when he came out with info?). 

That's a bad box of ammo, and not a gun problem.  At least, on the "pierced primers" side of the house.  His complaints went so sideways in this thread, like he always does, and now he's saying that all Hornady ELD-Ms must deform when you chamber them.  I haven't seen that accuracy problem that he claims at 1000 yards (from theory), and my common distance of really shooting at 850 yards (practical experience, not "theory").  Not in the least.  And, my .260 gas gun isn't beating up my 6.5mm Hornady ELD-M projectiles upon chambering, and denting any of the tips...   My accuracy at 850 yards with 6.5mm ELD-Ms is pretty fucking shocking, to be honest...  This gun blows my mind...  You can Mel Gibson-Lethal Weapon a smilie face on the head portion of an IPSC steel target at 300 yards, and it's actually funny to be able to do that.  @JBMatt built his own 6.5 Creedmoor gas gun just bacause of that, after shooting this .260...  He was playing around, and shocked himself... 

[98Z5V]

Read this thread, right here, to the end. When did I pierce primers?  Went too hot on a load, developing hand loads, is when.   Pretty hard to ignore this information, @Phantom30.  If I had a hardware problem, it would pierce primers all the time...   Hmmm...

If you STILL think there's some MASSIVE DIFFERENCE in 6.5 Creedmoor and .260 Remington - let's talk about that.  I'll bring you the information on the two, if you've ignored what I've posted previously. 

Edited July 28, 2019 by 98Z5V

[survivalshop]

    There ARE big differences in the two cartridges & no matter how close the two are they are different & I'm not talking about Performance out of the Barrel, since this thread is about damaging Bullets & pierced Primers . All of you should know by now , you really can't compare two different Cartridges or their mechanical feeding performance in a auto fed Firearm . The difference in the Shoulder angle & its length can cause issues , not to mention the tolerance stacking from one manufacture to another in the AR world , as this should be taken into account .

    Two issues & they are separate issues , one is pierced Primers , we can write it off & say its a bad batch of ammo or dirty chamber or Cartridge HS issue , yes even with factory ammo , it happens in mass produced Ammo, thats as long as it doesn't in the same Chamber with different Ammo . I have seen Bolt face FP Passages wear out with high pressure loads in very short order , it only takes a couple of Primer blow outs to gas cut a Bolt Face & FP Passage , not to mention the FP face itself .I could go on with tolerance stacking in this area also .

   The second issue is damaging Bullets & Bullet Tips , this is where you can't compare two different Cartridges , especially these two , their configuration are a lot different & their feeding characteristics will be different also , of course we can get into Bullet types & how that will effect feeding performance , this can also be where tolerance stacking can effect one Firearm manufacturer to another.

I never look at cut & dry problem solving , I always over think an issue , it may be a waste of time or it could help with the solution.  

 

[98Z5V]

1 hour ago, survivalshop said:

    There ARE big differences in the two cartridges & no matter how close the two are they are different & I'm not talking about Performance out of the Barrel, since this thread is about damaging Bullets & pierced Primers . All of you should know by now , you really can't compare two different Cartridges or their mechanical feeding performance in a auto fed Firearm . The difference in the Shoulder angle & its length can cause issues , not to mention the tolerance stacking from one manufacture to another in the AR world , as this should be taken into account .

No, there really aren't big differences between the two.  There's no way you missed that beautiful chart he made - those aren't big differences.

You must have missed this article I linked, as well. Here' the article again - not only read it, but make sure you look at the contained vid links in it, as well:

http://americanshootingjournal.com/260-remington-vs-6-5-creedmoor/

Just because I don't have a Creedoor, myself, you must mistakenly think that I've never been around one.  I have PLENTY of friends with them, and I've shot their guns.  They do not chew up ammo, just chambering it, and THEY have no issues hitting the 850 yar targets, either.  Explain that, SS, since you're the new champion of the cause in this one...

[98Z5V]

Here SS, lemme tell you a story about .260 Rem and 6.5 Creedmoor.   I have a 20" AR in .260 Rem. A great buddy has a Ruger Precision Rifle, bolt action, 26" barrel, in 6.5 Creedmoor.  We set up targets at 1000 and 1100 yards.  I check my dope chart info, I shoot first, and get on target. He says, "Hey, what did you dial for the 1000?"   I tell him, he dials, he shoots - and he's pretty damn close to the target.  Makes his minor corrections, and he's all over it. Next, he says, "What did you dial for the 1100?"  I tell him, he dials a little - and gets pretty damn close to the target, makes minor corrections, connects with the target.

So, if "There ARE big differences in the two cartridges" as stated, then how is the same projectile (147 ELD-M) in those two different cartridges...   able to almost use the same dope to hit at 1000 and 1100?...  

[survivalshop]

    There are big differences in the two , 20 deg. compared to a 30 deg. Case Shoulder angle  , I call that a big difference , when we are talking about a feeding issue . Its nice other's Rifles are shooting fine , but this one isn't , as said different manufacturers parts have a good potential to have tolerance stacking between said parts or components , just because one rifle shoots fine , doesn't mean another like it will . We are talking about large frame 308AR's .

As said , I'm not talking about Cartridge performance down range or right out of the Barrel or anything with Bullet comparisons .

[Phantom30]

The picture below is the range record for the "Hot Box" event.  The lot number is visible on the lid as previously reported.  The raised non-punched rounds are also displayed for

comparison on the 1st entry on this thread.  I can provide bolt face photos if desired.  They do have a rolled lip pin strike that sticks up slightly.  The round count of over 200 applies to this specific barrel, many others have been fired in other rifles.

 

[98Z5V]

6 minutes ago, Phantom30 said:

The picture below is the range record for the "Hot Box" event.  The lot number is visible on the lid as previously reported.  The raised non-punched rounds are also displayed for

comparison on the 1st entry on this thread.  I can provide bolt face photos if desired.  They do have a rolled lip pin strike that sticks up slightly.  The round count of over 200 applies to this specific barrel, many others have been fired in other rifles.

 

Great, now go back and tell me about that "Davidson" bolt you have now.  You replaced your bolt with a "Davidson" bolt, you stated.  Is this "Davidson" company that you're referring to Davidson Defense?  Is that the company you're talking about?...  

You're acting like that's an announcement that you stumbled upon?  Or an announcement that you made?  Because that's definitely "one of your charts" right there.

Edited July 30, 2019 by 98Z5V

[98Z5V]

On 7/28/2019 at 5:31 PM, survivalshop said:

    There are big differences in the two , 20 deg. compared to a 30 deg. Case Shoulder angle  , I call that a big difference ,

You can call that a "big difference" all you want, but that's not the ground truth, when dealing with both of them, out here in the practical world - shooting them.  I don't have friends with 6.5 Creedmoors having feeding issues - my friends don't have feeding issues with their 6.5 Creedmoor ARs - or bolt guns.  I don't have friends with 6.5 Creedmoors - that I shoot - damaging Hornady ELD-M tips and affecting accuracy "at 1000 yards" as the OP claims.  I've shot their guns, certainly at 850 yards repeatedly, and at 1k and 1.1k a few times. 

I'm on a different side of the fence than you are SS - you're dealing in theory, like the OP is.  I'm dealing in reality, and practical application here, between two cartridges.  Similar case volume, same base diameter, same projectile, similar powders and case charges...    You can talk all you want, support all you want - I'm telling you that the differences that you "think" might be here between the two rounds isn't nearly as drastic as you "think" they are - they're pretty negligible, when you get the guns out there and make them work.  I've already done it, brother.  Holy shiit, I can give a 6.5 Creedmoor shooter - on a drastically different gun profile - MY drop data to hit targets at 1k and 1.1k yards - and he makes a 1st round shot that's damn near on-target at those distances?  And you're gonna tell be about the "big differences" between those two rounds?  It doesn't exist...

You obviously didn't read the link - and the links within - that I left for you.  If you had, you'd understand that your argument makes little sense...    

[survivalshop]

10 hours ago, 98Z5V said:

You can call that a "big difference" all you want, but that's not the ground truth, when dealing with both of them, out here in the practical world - shooting them.  I don't have friends with 6.5 Creedmoors having feeding issues - my friends don't have feeding issues with their 6.5 Creedmoor ARs - or bolt guns.  I don't have friends with 6.5 Creedmoors - that I shoot - damaging Hornady ELD-M tips and affecting accuracy "at 1000 yards" as the OP claims.  I've shot their guns, certainly at 850 yards repeatedly, and at 1k and 1.1k a few times. 

I'm on a different side of the fence than you are SS - you're dealing in theory, like the OP is.  I'm dealing in reality, and practical application here, between two cartridges.  Similar case volume, same base diameter, same projectile, similar powders and case charges...    You can talk all you want, support all you want - I'm telling you that the differences that you "think" might be here between the two rounds isn't nearly as drastic as you "think" they are - they're pretty negligible, when you get the guns out there and make them work.  I've already done it, brother.  Holy shiit, I can give a 6.5 Creedmoor shooter - on a drastically different gun profile - MY drop data to hit targets at 1k and 1.1k yards - and he makes a 1st round shot that's damn near on-target at those distances?  And you're gonna tell be about the "big differences" between those two rounds?  It doesn't exist...

You obviously didn't read the link - and the links within - that I left for you.  If you had, you'd understand that your argument makes little sense...    

How do you figure its theory when he is having feeding issues & Bullet deformation , how is that theory ? Trouble shooting an issue with a Firearm you can't see or get your hands on , is a lot of theory , no choice .

 I 'm going to repeat myself again , because you are have a hearing issue , I never once said anything about the performance of said Cartridges or their performance in the Barrel or out of it . Thats for you & him to puff out your chests about . 

You go ahead & quote all you want , if you don't think a 10 deg. in Shoulder angle isn't a big difference & doesn't effect feeding of a Cartridge , you need to read more or go back to school . As I have said again , the problem is with this particular Rife & not 8K others .

What you build a few AR's & now you're an expert on all things Firearms related , Ok professor , maybe you should start designing them , I'm sure you will make a fortune .

& yes I can say this because I am a Gunsmith & have worked on hundreds of different types of Firearms for over forty years & repaired them ! You seem to belittle just about anyone that has an issue if it doesn't fall into a cut & dry fix or that doesn't agree with your said fix . Good luck