375 SnipeTac hangfires

[6Dasher]

Hi,

Just starting to play with my 375 SnipeTac and did some tests to see what the limit was on the charge.


Setup:
Lawton 8000
34" 1:8 Bartlein
Bertram cases, fireformed with CoW
CE 402MTAC & GS 414 bullets
Vihta N570 ±140gr



On the first run with CCI 250 (LRM) I noticed some hangfires, about 50%. It's tik-BANG, so only a few milliseconds. Read up on the primers where everyone advised Fed215 because of this, so I tried those next. I'm getting the same number of hangfires with the 215 and was wondering if there is a hotter primer out there to try and see if this is the problem? At 100 it will not group at all, about 1moa horizontal and 3-4moa vertical; this being from a bipod I acredit the 1moa to myself, but the big elevations I am looking towards the hangfires. Have not done velocity measurements yet, so don't know the spread on this load. Only did about 8 rounds, will load up some more and check speed next time.

Other tips welcome as well.

 

[wadcutter]

Try another powder.
50BMG would be what I would try with those pills. It works ok in my .375 CT with 375gn bullets.

 

[6Dasher]

Hard to get here, but will give it a try if I can get my hands on a can.

 

[jmason]

I don't know if it will help but Winchester primers throw more heat.

 

[DAVETOOLEY]

I've had Wolf primers do that. I should know better but I wasn't seating the primer firm enough to sensitize it. The firing pin would fall and ignite one side of the priming compound under one anvil and in a few milliseconds the rest of the compound would light off then the powder. I have seen one other cause for hang fires. Large capacity cases with reduced charges being loaded single shot with the cartridge nose down putting the powder charge in the front of the case.

 

[milo 2.0]

I've had Wolf primers do that. I should know better but I wasn't seating the primer firm enough to sensitize it. The firing pin would fall and ignite one side of the priming compound under one anvil and in a few milliseconds the rest of the compound would light off then the powder. I have seen one other cause for hang fires. Large capacity cases with reduced charges being loaded single shot with the cartridge nose down putting the powder charge in the front of the case.

I've seen the second part of Dave's theory also, but 140gr of 570 should be plenty of volume, big kernel stuff. I suspect the primer also.

A hangfire in any gun is scary, in that case, off the charts!

 

[Chandalar]

Had good success for Federal 215's and Retumbo with Sierra 350 MK's @ 3115 (375 Cheytac) , Also had good experiences with H50 bmg and Fed. 215s in a 338 Snipetac. Very good stout ignition with both calibers and the Fed 215s.

 

[Dogtown]

If you're getting the same hangfires with CCI 250s and Fed215, then something is definitely wrong and it's probably not the primers. The first thing I'd check is to make sure your flashholes are all clear of tumbling media (hey, it happens) and more importantly, make sure you're seating the primers deep enough. I love using the K&M primer with dial indicator so that I can go off of an actual measurement and not just feel.

 

[zenbiker]

If you're getting the same hangfires with CCI 250s and Fed215, then something is definitely wrong and it's probably not the primers. The first thing I'd check is to make sure your flashholes are all clear of tumbling media (hey, it happens) and more importantly, make sure you're seating the primers deep enough. I love using the K&M primer with dial indicator so that I can go off of an actual measurement and not just feel.

If it hasn't been mentioned already, I'd uniform the flash holes on all my brass, including deburring the inside of the flash hole and the depth of the seat - Ken Markle used to make a great set of tools for that. Some flash holes are punched, not drilled, and the burs inside will slow the primer flame propagation into the powder. Last, and this sounds nuts, but be sure your load fills 90% or better of your case; too little powder can result in a hangfires and in extreme cases where the load density is only around 50 percent, can cause a dangerous spike in chamber pressure.


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[steve123]

If it hasn't been mentioned already, I'd uniform the flash holes on all my brass, including deburring the inside of the flash hole and the depth of the seat - Ken Markle used to make a great set of tools for that. Some flash holes are punched, not drilled, and the burs inside will slow the primer flame propagation into the powder. Last, and this sounds nuts, but be sure your load fills 90% or better of your case; too little powder can result in a hangfires and in extreme cases where the load density is only around 50 percent, can cause a dangerous spike in chamber pressure.


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I agree, high load density makes for better ignition in those huge cases. Retumbo and 215M is what worked well in my 375ct.

 

[wadcutter]

Hard to get here, but will give it a try if I can get my hands on a can.

What about 20N29 or 24N41 powders? They may be more available in the Netherlands???

 

[Master Diver]

N570 is perfect for the 375 SnipeTac along with Fed 215 primer it should work perfect every time. I use that combo myself for years and have never had any hangfires. 140 grn must be close to a compressed load with the 414 SP bullet from GSC so density is not the problem. I use GSC SP 355 grn and 136 grn of N570, V0 is 3200 and accuracy is 1/8 moa at 100m and like in the picture below at 600m
I also think it could be a flash hole problem. I see in the picture that you use BB = Bertram Brass. I had some problems with BB in cal .500 Jeffery, the quality of the brass was poor. The problem was that the brass was to thin and would not hold the bullet tight. They where also a bit short. How that passed quality control was a great surprise to me.
Try SnipeTac brass from Dieter Horneber. He makes the very best cartridges - that way you also don't have to fire-form.

Cheers,

Master Diver

 

[VaRandy]

You mention Dieter Hornebar....Does he offer .408 cases as well? If so how do I reach him.

 

[agbm]

You mention Dieter Hornebar....Does he offer .408 cases as well? If so how do I reach him.

Here you go website:Hülsen - Horneber

 

[Black Diamond Rifles]

I have experienced hang fires with ball powder in cold weather. I have never seen any using Retumbo or BMG50 powders. Check your flash holes and make sure the primer is seated firm to the bottom. Also make sure the primers are fresh. I had a customer complain once and he found that the primers were causing the issue.

Dave

 

[Dogtown]

You mention Dieter Hornebar....Does he offer .408 cases as well? If so how do I reach him.

In the early days of the .408CT (2002-2006) when components were near impossible to acquire, the Horneber brass was highly sought after, but as far as I know it's still hard to get in any volume regularly?

Maybe by 2020 the popularity of .375CT will be enough for Lapua to start production

 

[hognuts]

I had hangfires in my 375 Cheytac with H-1000 running the Tula Magnum primers. I have been running Remmington Primers and haven't had an issue since. What I was told is that when you get over 100 grains of powder, primer selection becomes important. I found an artice somewhere that lists them in order of "hottest" to "shittiest" basically, but what was weird was the CCI's were fairly high on the list but you are not the first one I have heard of that has had issues with them. I am running Remmington now and they work great, I have about 4000 Winchesters as well, hoping they will work, once I get through the Remmingtons.

 

[6Dasher]

Thanks for all the answers guys!!!!

140gr of N570 is 95% full on the 402MTAC. I also have 24N41 here to play with, but it's even slower than N570.

Neck tension seems to be okay, not light, not heavy.

Primer: I use a sinclair primer seater and can feel the primer bottoming out each time, but I will try uniforming them all and putting them in a bit tighter, also ream up the hole with a .082 tool to make sure they are all the same. I have some Winchester primers somewhere, will try those too. Did the same experiment on the Lapua 308 Palma cases that gave hangfires as well.

Horneber brass: I contacted them several times but never got an answer. I gave up and got 200 Bertram cases in the US together with the rifle. Horneber would be ideal as it's in the EU and less hassles/cheaper to get here. Fireforming is just a pita, not expensive though, just the CoW method, so an extra shooting session is all.


Will Federal ever release the 216?

 

[DAVETOOLEY]

I'd advise not to uniform them. Making them deeper can lead to unintended consequences. Misfires caused by the firing pin protrusion. The primer and the pocket are the crudest least critical subsystem of the round. The primer has to be seated hard enough to sensitized it and struck with enough force by the firing pin to ignite it. That's it.

Just an off the wall question. When you dry fire the rifle what does it sound like? A crisp ring, a sluggish squish, something in between?

Here's something I did actually by mistake the first time. In an attempt to deburr the flash hole from the inside I enlarged the flash hole and put a pretty significant chamfer on it. It shot great. I started putting a chamfer on all my cases used in competition. I wouldn't enlarge the flash holes but you might explore cutting a chamfer which in theory would allow the flame to widen somewhat after it passed through the shorten flash hole.

I use Sinclair tools also and find once I hit bottom it still requires a bit more travel to fully seat the primer.

 

[6Dasher]

Dave,

What I recall from dry firing (and I will check when I get home) is that is is crisp and quick "TACK!". It's a long bolt, so there is quite a bit of force when it goes off. he time between strike and ignition is always in the msec range, and always the same. On the 308 palma it varied a lot, from almost nothing to powder not igniting and clumping up. None of that on the CT, I can just hear the pin striking before the case goes off (tack-BOOM).

I'll try chamfering 5 cases first to see if this helps. The sinclair tool also reams the hole to .082. Not too large. Also the sinclair uniformer only takes out a little while uniforming. My WSM brass gives off way more brass then the Bertram cases.


Things I will try next time out
- chamfer inside flashhole
- seat primers harder
- try winchester primers in combination with above if 215 still won't work

 

[6Dasher]

Finally made it out to test some loads again. I seated the primers tighter but did not have a deburrer for the flashhole that would chamfer decently. Loads of 139 tot 140.5gr, 12 rounds in total and not one hangfire. Maybe it's the primer seating that gave the problems.

Groups are about 0.5moa now at 100m, will test speeds on the next trip out (left the magnetospeed at home).

 

[HodgdonExtreme]

At the risk of being flamed for saying such a thing...

A friend has a 500 A-squared, which is a 460 Weatherby parent, increased to .510". He was having persistent hang fires and did a bunch of reading, to learn it's pretty common practice to drop a couple of grains of pistol powder into the case first, followed by the full charge of slow rifle powder. It's very important you are using a COMPRESSED charge using this technique - to ensure the "duplex charge" stays layered and stratified.

Of course, before trying this, perform your own due diligence and research.

 

[Alphabet]

In all most every case of hang fire I have ever seen or experienced myself it was due to lack of proper primer seating and/or flash hole obstructions. Case fill/volume also has a large effect on proper ignition as a completely full 100% or even a 105-110% compressed charge of lets say BMG powder will give extremely great performance verses a 90% fill ratio. In most cases you will have lower case pressure with a higher %age of case fill then with a lower %age.

 

[RussW1911]

Didn't read the whole thread, but CCI primers are not what you want to be using for these large capacity rounds. Stick with Remington and Federal Magnums.

 

[Alphabet]

Didn't read the whole thread, but CCI primers are not what you want to be using for these large capacity rounds. Stick with Remington and Federal Magnums.

What are you seeing with the CCI's my fellow Gunny

 

[Kiwi Greg]

What are you seeing with the CCI's my fellow Gunny

215s a brighter/stronger than 250s & softer in the cup.

 

[6Dasher]

I just came back from a trip to a 1600m range. Had 52 rounds with me of the 375 and had 2-3 hangfires (only a few milliseconds though). I was shootin the 402CE at 3105fps with a load of 140.5gr N570. That's about 90% full I guess. All of the primers were seated hard, no burs in the flashholes. Will try to chamfer out the insde of the flashholes a little to see if that helps.

 

[steve123]

I think if I were to play with a 375CT or a wildcat based off the cartridge I would experiment with a duplex load using pistol powder like someone described earlier. Back when I had mine every once in a while I'd get a delayed fire. That was as sorted out as I could get a load in my rifle and with lots of trying. I wonder if short firing pin protrusion might help cause this problem.

 

[6Dasher]

A 300NM on the same action doesn't have the problem.

Duplex loads are a no-no. Besides the safety issue, it's near impossible to keep them seperated and will cause havoc on ES/SD. This is a solution with more problems then you are trying to solve.

 

[Kiwi Greg]

I think if I were to play with a 375CT or a wildcat based off the cartridge I would experiment with a duplex load using pistol powder like someone described earlier. Back when I had mine every once in a while I'd get a delayed fire. That was as sorted out as I could get a load in my rifle and with lots of trying. I wonder if short firing pin protrusion might help cause this problem.

The only time I've had a hang fires is with not enough US869 in cases, 338 Imp, CT imp & CCI 250s.

A duplex as mentioned could bring more inconsistencies ?

 

[steve123]

I used 250M's, US869 which is temp sensitive, H-870 same sensitivity and Retumbo, 3 different projectiles, different seating depths. Retumbo worked the best.

A friend built his at the same time with similar results. These are the only two I've shot but over the years I've seen more than a few threads about this very subject specific to 375CT and it's variants.

I don't think I'm out of line here with the notion that 132+ grains of slow powder doesn't ignite with full and uniform ignition consistently with a hot magnum primer. Nevertheless you guys are probably right about the duplex load bringing another set of problems to the table.

How about the 408 and 338 imp, do they ignite more consistently?

Edit...Maybe a CT case shortened a 10th a inch would ignite better???

 

[6Dasher]

I hope Federal releases the 216 someday soon. It's a hotter variant of the 215. Another option would be the CT cases with 50BMG primer.