22 creedmoor barrel/load question

[oldfarmer]

Last November I had my first custom bolt gun built. Defiance Deviant Tactical action, 20” proof carbon 1:7 twist barrel, KRG bravo stock. 42.8 gr of H-4350 would put the Berger 80 Vld or 80 eldm in 1/4” to 3/8” 5 shot groups at 100 yards. After about 50 rounds these loads went to 1- 1 1/4” groups. Now I’m having to run 39 gr. H-4350 (3185 FPS) to keep the groups less than 1/2” at 100 yards. Anything hotter and the groups open up to 1 1/4”. I tried with and without suppressor with no real change in group size. I know barrels speed up over time but I didn’t know if accuracy changes like this were normal? Barrel has been cleaned thoroughly and checked with borescope several times to make sure there aren’t any issues with build up. I know the initial loads were perfect on coyotes which resulted in them dropping in place with violent expansion. My concern is that with the 39.0 gr load, I’m not sure the velocity will be high enough to see the rapid expansion that I saw with the 42.8 gr load. So my questions are is it normal to see that a load has to be changed so drastically after the barrel speeds up and does anyone have any experience with these 2 bullets performance at <3200 FPS on game? Thanks in advance





Load currently shooting



Load currently shooting





After 50-75 rounds




Initial testing




Initial testing




Group shot after around 50 rounds below

 

[Kocher]

So what is the speed difference 3100 @38 gr 4350 versus what @42.8 gr=?

FYI. 41.7 of 4350 hodge Is max load @ over 62,000 psi!

I’m not saying that you don’t know this but running it at that hot it’s gonna shred that nice barrel very quickly (imho)

I’m no expert nor do I claim to be. I will be soon running the same action as a different barrel but I do not want to be running it that hot at first.

But if I had nice groups like you’re getting @38grns? Dang.. that is money. I don’t know the reason why it opened up but I would say that perhaps it’s the obvious and it just doesn’t like to be run with that bullet at that speed anymore you could try a different bullet but that’s just harmonics I guess.

And I don’t think you have anything to worry about, that bullet is not a hunting bullet and they can be quite inconsistent no matter what speed you’re running..

I am like you though and I would sit and worry about it the good thing is you did have someone put that together for you I would contact them and ask them what is going on?

 

[triumph001]

The white paper Peterson put out (lol say that fast three times in a row) indicates that you are overpressure with 42.8 grains of 4350 and that bullet. If you want to go faster you might end up having to choose a lighter bullet. Where did you get your initial load data?

Might want to reference this document if you havent yet.

https://www.petersoncartridge.com/media/1367/22-creedmoor-press-release.pdf

 

[Kocher]

The white paper Peterson put out (lol say that fast three times in a row) indicates that you are overpressure with 42.8 grains of 4350 and that bullet. If you want to go faster you might end up having to choose a lighter bullet. Where did you get your initial load data?

Might want to reference this document if you havent yet.

https://www.petersoncartridge.com/media/1367/22-creedmoor-press-release.pdf

That WPP...is also, what I was referring to as well.

80 Grain Berger VLD Target COAL: 2.600” Primer: Federal Large Rifle Magnum Match (GM215M) Powder Type: H4350 Powder Charge Weight: 40.5 Grains Velocity: 3,500 fps Pressure: 77,343 psi (This is over pressure do not use) "WPP REF"


@ 42.8 gr of 4350. you would be 2 what, 90,000 PSI ??? That is some scarry shit.
as 41.5= 80,000 psi?

I am a beginner when it comes to Rifle cartridges, and a gosh darn 2nd class citizen when it comes to dealing with wildcat, overbore reloads.
These over bore setups get nasty very quickly. Even the pussy cat, 17 Hornady, gets you in trouble if you are not careful.

 

[oldfarmer]

Thanks for the replies guys. Sounds like it’s a good thing it doesn’t like that load anymore. I had looked at the Peterson info but worked my way up looking for signs of pressure along the way. I didn’t realize until later that the alpha SRP brass doesn’t seem to show a lot of flat primers or other normal signs of pressure like most of the other cartridges that I load for. A few of my friends run basically the same gun that was chambered using the same reamer as mine. 3 of their rifles are shooting the same load (43.2 gr H4350) in one hole groups, so that’s why I was initially working my way up before landing at the 42.8 gr load. After reading the above posts I have told them about what has been said about those loads being wayyyyy above safe pressure. On a brighter note, I bought a pretty good deal in 500 73 gr eldm bullets and my rifle shoots them extremely well at 41.0 gr of h4350. I haven’t been able to shoot a coyote with this bullet/load yet but hoping it will be devastating on them. Does anyone like the 73 eldm for coyotes?

 

[KnowNothing256]

Is it possible you’re over-spinning the bullets? You’re at 327k rpm, and Proof bores tend to be a bit tighter, leading to more jacket deformation and more susceptibility to issues such as blow-up. I know you’re not saying you’re popping bullets, but the first thing I thought before even getting through the first paragraph was “that’s a pretty fast twist for that cartridge.”

ETA: Over-spinning at higher charges/velocities, I mean

 

[Kocher]

It is pretty cool though.. just sayn.
It is very good brass/action to be pushing it that hard and no brass issue!

I was blowing up 55grn Sierra blitz kings at only -3700fps approx with a1/7 twist in my Ar10. Guys like the 22CM for the heavies though, so open selection w/o custom barrel is nadda.

 

[Cynical]

Man I don’t know how you didn’t have pressure issues. I had a somewhat sticky bolt lift and ejector intentions on Alpha SRP OCD brass with 77gr Berger otm loaded with 42.2gr H4350. I backed it off to 42.0 and the bolt lift is maybe slightly above normal (let’s call normal 41.6gr). Maybe. It shoots well. Primers look flat but fine.

I just can’t imagine 43+ grains with a heavier (80gr) bullet.

 

[oldfarmer]

Yeah looking back it’s kind of crazy that it didn’t show any issues. I have ran lapua SRP, Alpha SRP, and Hornady LRP brass with no sticky bolt issues. I did have a few pieces of the lapua that the primer pockets got a little loose after 3-4 firings but that was it. Has anyone tried the 73gr eldm on coyotes? Or do you have a better bullet that you could recommend?

 

[Kocher]

New PRS rifle for old benchrest shooter

Is Hornady's 6mm ARC in a bolt gun a viable choice as a beginner rifle for PRS/PRL? Would 6BR, 6GT, or even 6 Creedmoor be a much better choice for a newbie? Since I plan to run suppressed, I would like to keep the barrel length to 22" or even 20". Many years ago I competed in benchrest...

www.snipershide.com

I would highly recommend you read through this post is very informative about powders pressures and concerns about loading over what is safe

 

[Kocher]

I will be rethinking all of my loads, as being out in 100+ degree weather on the range is a MAJOR change compared to the 20deg F that I developed the loads in for my 17Rem AR15 and 22-250.

For the 22CM, It is difficult because with this load there really isn’t any manuals that show it even the Hodgedon website shows the reloading manual online for the 22 Creedmoor but it does not include the major powders that people use (4350-type powders ). Whether it’s the IMR, Hodgdon, shooters world, why they don’t have those on the list is beyond me? Perhaps they feel no one can find it to purchase so don’t include it? “Vexing, I’m deeply vexed” They do show “hunter” powder but that was it.

This doesn’t do shooters any favors but after all it is still a wildcat.

I got word my Defiance anti-x action has arrived at the dealer!!!! Woohoo. Never had a custom action, let alone a precision rifle!

Will be using the shillen remy barrel nut system for the 22CM barrel.
The barrel however is Not profiled to loose weight, or have a threaded end on it. Hence the inexpensive price on the barrel when compared to the 800$ that most charge for a CF or lightened barrel.

Exciting times.

 

[triumph001]

Yeah looking back it’s kind of crazy that it didn’t show any issues. I have ran lapua SRP, Alpha SRP, and Hornady LRP brass with no sticky bolt issues. I did have a few pieces of the lapua that the primer pockets got a little loose after 3-4 firings but that was it. Has anyone tried the 73gr eldm on coyotes? Or do you have a better bullet that you could recommend?

What performance traits are you wanting out of the bullet? I assume you arent keeping fur if you are using a 22 creed.

Bottom line with the kind of speed you get out of a 22 creed any target or hunting bullet that weighs more than 70 grains will kill coyotes. Unless you are trying for texas heart shots. Shoot a couple and report back.

 

[Kocher]

I started thinking about that comment as well as far as whether or not such a bullet would be fast enough ect.

some people hunting coyotes with a 17 WSM or even a 22 LR not my cup of tea. I’ve also seen and heard of bullets being too fast doing massive splash damage causing it looks like a horrible death.

As I get older I have a hard time killing something especially when it looks like my best friend. Whether it’s a deer= looks like a golden retriever or lab. To coyotes that look well, like a dog.

I think a lot of us get hung up on all these things about loads and speed but yet we don’t really get out and experience the hunt being out in the wilderness on a prairie doing it, and shot placement means more than anything and we should be practicing Odd angle shots sitting on the floor in the field type shots more than concentrating on load informatio. All the loading the world won’t do shit if you can’t even hit something when you’re not on a bench rest.

Again I’m probably speaking out loud to myself on this more than the original poster but at least got my mind turning.

 

[oldfarmer]

I have shot a few with the 80 gr Berger and 80 gr eldm and both killed just fine. The issue I was seeing, especially with the Berger was that even with good shot placement some would make it 30-40 yards into some thick brush, briars, etc. Some of the places we hunt aren’t large fields, but other areas may require shots over 400 yards. To most people I’m sure a coyote running 30-40 yards isn’t a big deal. To me it isn’t as big of a deal as it used to be, but when we hunted a lot of contests the additional time to track/recover really adds up. This was the original reason we started hunting with the 6.5 CM running 95 gr vmaxes. We were looking for something that most of the time caused them to DRT, and if they ran there were no issues finding a blood trail. My main complaint with the 80 gr eldm and Berger were that they didn’t leave the huge exits that I was accustomed to while contest hunting. Those performed similarly to a SP or other deer hunting style bullet. I guess I’m just being overly picky but getting in and out of a stand in 10-15 mins including drag time made the difference in placing or not.