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Phantom30

Primer Puncture

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11 hours ago, Phantom30 said:

Thanks SS the bolt change recommendation solved the problems.  Switched from the 308W Toolcraft single ejector NIB BCG to the Toolcraft 6.5CM small tip FP 0.065" instead of 0.077" plus dual ejector.  Plus thoroughly clean chamber more often with 308W AR brushes and mop.  All is now well, shooting sub-MOA with my cheapest parts I can find DIY built rifle.

You still sending Hornady your data on their defective ELD-M tips that dent and break when chambering?...   :popcorn:

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The one time test and data was sent to Hornady in July 2018.  Never said break.  The dents would probably have a minor effect on ballistics since the spin rate is so high and the mass of the plastic low.  On the other hand where the tips were lead the deformation effected the mass distribution and dramatically demonstrated the effect.  Granted those tips should not be used in an AR format but the effect changed concentricity and opened up accuracy.  The point of the Lead tip test is to demonstrate that the forces encountered during chambering where significant.  Copper OTM or HP although a much harder material still cold produce a flyer on occasion.  Your vast experience with 260 Remington is not the same as the chambering issues with a Creedmoor.   Recommending a Toolcraft BCG is a good thing but for a Creedmoor since it has been reported to have ejection and primer punch issues, the recommendation should include the high pressure 6.5 CM specific versions, single or dual ejector.   In the velocity measurement chart it was noted that the post burn thru shot primers were all burred, on either brand of ammo used.  This would indicate that the burn thru jetted the FP hole in the bolt face making it unsafe.  The image of the primers fired using the new bolt installation shows a nice small strike pockets.  Both ammo lots were tested with the new BCG, one fired hot lot ammo primer did show a slight ridge.  No chronograph was allowed during this verification exercise so you couldn't attribute a velocity to that casing. 

Lessons learned here is that vendors advertise their BCGs will work in Creedmoor ARs, I am sure that's true but to be fully truthful the BCG should be the type spherically designed for the Creedmoor AR.

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9 hours ago, Phantom30 said:

The one time test and data was sent to Hornady in July 2018.  Never said break.  The dents would probably have a minor effect on ballistics since the spin rate is so high and the mass of the plastic low.  On the other hand where the tips were lead the deformation effected the mass distribution and dramatically demonstrated the effect.  Granted those tips should not be used in an AR format but the effect changed concentricity and opened up accuracy.  The point of the Lead tip test is to demonstrate that the forces encountered during chambering where significant.  Copper OTM or HP although a much harder material still cold produce a flyer on occasion.  Your vast experience with 260 Remington is not the same as the chambering issues with a Creedmoor.   Recommending a Toolcraft BCG is a good thing but for a Creedmoor since it has been reported to have ejection and primer punch issues, the recommendation should include the high pressure 6.5 CM specific versions, single or dual ejector.   In the velocity measurement chart it was noted that the post burn thru shot primers were all burred, on either brand of ammo used.  This would indicate that the burn thru jetted the FP hole in the bolt face making it unsafe.  The image of the primers fired using the new bolt installation shows a nice small strike pockets.  Both ammo lots were tested with the new BCG, one fired hot lot ammo primer did show a slight ridge.  No chronograph was allowed during this verification exercise so you couldn't attribute a velocity to that casing. 

Lessons learned here is that vendors advertise their BCGs will work in Creedmoor ARs, I am sure that's true but to be fully truthful the BCG should be the type spherically designed for the Creedmoor AR.

Looking at a 6.5 Creedmore build in the future. This is good to know. Thank you.

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21 hours ago, Phantom30 said:

The one time test and data was sent to Hornady in July 2018.  Never said break.  The dents would probably have a minor effect on ballistics since the spin rate is so high and the mass of the plastic low.  On the other hand where the tips were lead the deformation effected the mass distribution and dramatically demonstrated the effect.  Granted those tips should not be used in an AR format but the effect changed concentricity and opened up accuracy.  The point of the Lead tip test is to demonstrate that the forces encountered during chambering where significant.  Copper OTM or HP although a much harder material still cold produce a flyer on occasion.  Your vast experience with 260 Remington is not the same as the chambering issues with a Creedmoor.   Recommending a Toolcraft BCG is a good thing but for a Creedmoor since it has been reported to have ejection and primer punch issues, the recommendation should include the high pressure 6.5 CM specific versions, single or dual ejector.   In the velocity measurement chart it was noted that the post burn thru shot primers were all burred, on either brand of ammo used.  This would indicate that the burn thru jetted the FP hole in the bolt face making it unsafe.  The image of the primers fired using the new bolt installation shows a nice small strike pockets.  Both ammo lots were tested with the new BCG, one fired hot lot ammo primer did show a slight ridge.  No chronograph was allowed during this verification exercise so you couldn't attribute a velocity to that casing. 

Lessons learned here is that vendors advertise their BCGs will work in Creedmoor ARs, I am sure that's true but to be fully truthful the BCG should be the type spherically designed for the Creedmoor AR.

Based on what you're saying, have you compared pressures between 6.5 Creedmoor and .260 Remington?  Do you know the differences, in operation, besides what you posted about the external cartridge-case dimensions?  Having said that, with pressures being almost identical...  why have I not seen this in any .260 Remington that I've loaded  - besides those hot 130s that I loaded up?...   I posted a link to them... 

I'm using a .308 BCG, not a 6.5C BCG.  I should be seeing the same things you're seeing, if what you're posting is some kind of "evidence..."...

Edited by 98Z5V

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21 hours ago, Phantom30 said:

don't know much about a 260 Rem other that the public SAAMI

That's pretty apparent. 

So, did the new bolt with the dual eejctors work better than that Davidson Defense bolt (which is a blem from SOME manufacturer) work better for you?...  :popcorn:

SS recommended you a bolt, and you went with it - and you're saying it's better performing than that "don't know what the blem was" Davidson Defense bolt was. Is that right?...

Or, are you talking about a different gun this time?... 

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Davidson Defense bolt is working fine in the 24" rifle.  Although I don't know if it would punch primers as the Toolcraft NiB 308W BCG did in the 22" rifle with the same hotter ammo lot.  The 24" rifle now has the benefit of the nice Toolcraft NiB carrier from the damaged BCG instead of the old KAK carrier.  Eventually the 24" Toolcraft carrier with Davidson Defense bolt BCG will be replaced by another Toolcraft 6.5 CM specific dual ejector BCG when the funds are available.  This exercise has highlighted the fact that 6.5CM has caliber unique issues and has the potential for problems when using a standard AR-10 308W BCG.  Therefore, it is obvious that if a company like Toolcraft has developed, produced and distributed a 6.5CM specific BCG then any 6.5CM AR builder should consider that fact and go with the BCG designed specifically for that caliber rifle.  Both single and dual ejector models are available but since the caliber is reported to have potential ejection issues, then way not just go with the dual ejector and be done with it.  The Toolcraft dual ejector design is different then other dual ejectors and I would suspect, if you may, that they did it right.

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On 8/24/2019 at 5:32 AM, Phantom30 said:

Davidson Defense bolt is working fine in the 24" rifle.

You ever identify what the blem was in that bolt?  It's there, whatever it is - since that's all they deal in is Blem Parts.

Good Luck.  :thumbup:

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Ok I just read this whole thread, and I take it since my 6.5 CM upper is almost done that i need to buy a new bolt just for 6.5 CM if that is the case is the toolcraft bolt a good bolt or a bargain bolt and if the latter what bolt would anyone recommend... or should I try my 308 bolt it is sub 1/2 min for 308 with Barnes 168TTSX .. thanks

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13 minutes ago, Magwa said:

Ok I just read this whole thread, and I take it since my 6.5 CM upper is almost done that i need to buy a new bolt just for 6.5 CM if that is the case is the toolcraft bolt a good bolt or a bargain bolt and if the latter what bolt would anyone recommend..

I would run it first and see if you have an issue. If you decide you need a high pressure bolt take a look at Fulton, they have a sweet looking bolt for a real fair price. 

https://www.fulton-armory.com/bolttitanstripped-1-1.aspx

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15 hours ago, Magwa said:

Ok I just read this whole thread, and I take it since my 6.5 CM upper is almost done that i need to buy a new bolt just for 6.5 CM if that is the case is the toolcraft bolt a good bolt or a bargain bolt and if the latter what bolt would anyone recommend... or should I try my 308 bolt it is sub 1/2 min for 308 with Barnes 168TTSX .. thanks

The pressure in any 6.5C round isn't blowing the doors off the pressure in my .260 Rem handloads, and I'm just running a ToolCraft .308 BCG, complete.  It does just fine.  :thumbup:

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6 hours ago, 98Z5V said:

The pressure in any 6.5C round isn't blowing the doors off the pressure in my .260 Rem handloads, and I'm just running a ToolCraft .308 BCG, complete.  It does just fine.  :thumbup:

👍

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brother i ran the .308 bolt and had minor problems that weren't apparent but switched out to a tool craft bcg doul ej and it solved all my issues less my scope mount failing.. food for thought don't spend to many rnds.. 👍

On 8/28/2019 at 3:59 AM, Magwa said:

Thanks I will try my 308 Bolt first then get another if I need...

 

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