Chrony of Truth

The place to discuss ammunition, reloading, ballistics, loads, and chamberings.
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Gunnuts
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Re: Chrony of Truth

Post by Gunnuts »

HTRN wrote: Wed Aug 15, 2018 12:03 am
Netpackrat wrote: Tue Aug 14, 2018 7:38 pm
No personal experience, but I have heard they lose their shit on a range being shared with other shooters. I was seriously considering getting one before I heard that.
I just did some checking, an supposedly A) the system is smart enough to detect what is your shot, and what isn't, and B) is adjustable for sensitivity and frequency. Tke that with a grain of salt though..
I went all in when they had their sale in June.

Haven't had an opportunity to try it out yet, but I'll give y'all a report when I do.

Don't hold your breath though.

My primary range has been taken over by lib gun gamers who reserve the vast majority of the range the vast majority of the time for themselves.
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Netpackrat
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Re: Chrony of Truth

Post by Netpackrat »

As noted in Does Not Follow, I did a bunch of chrony testing yesterday. I am not going to post all the chrony data since it mostly pertains to my rifles alone, but I have at least one observation that might be of interest. Rifles were a 16" AR that I recently finished that is made with an AAC pistol gas barrel, .081" gas port, the second was my 10" SBR using an Aero upper with (of course) pistol gas an an .098" gas port (very slightly enlarged over how Aero supplies it), and lastly my 16" bolt action, also built on an AAC barrel and Remington action. Similar in configuration to the factory Model 7 that Remington built with the same barrel, but I put it together myself. Both 16" guns were the result of having found those barrels deeply discounted and then building rifles around them. :lol:

I loaded 2 different bullets; the first was the standard Sierra 220 grain Matchking that everyone uses (though these are silver colored, came in a 500 piece bulk pack from American Reloading on sale), and the second is the Lapua 220 grain Scenar-L. The Lapuas are normally a VERY expensive bullet that you would ordinarally never lob into the dirt at 1000fps, but I found them HEAVILY discounted at Graf's and ended up buying 1000 of them. I loaded up 20 round batches of each at 3 different charge weights of A1680 powder, beginning at the 11.2 grain starting load that I believe originated with AAC when they created the cartridge, and then some at 10.8 and 10.4 grains each, for a total of 120 rounds. 5 of each combination for chrono testing with each rifle, and 5 of each for groups at 100.

Maybe the most interesting thing from the data to me is that the action type had a much greater effect on velocity than the barrel length did. I expect the results would be different for supersonic ammo, but between the 16" bolt action and the 16" AR, there was usually around a 50fps difference, while between the 16" AR and the 10" AR it was generally 15fps or less.

I only loaded up one supersonic test load. A couple years ago I bought 5 boxes of the same 110gr black tip bullets that Barnes loads in their factory ammo, again because they were on sale. I loaded 25 of them up in 5 round batches increasing in .5 grain increments of W296 powder, using the H110 data for that bullet from Barnes (it is well documented that they are the same exact powder in different packaging, Google it if you wish). I also fired 5 rounds of factory Black Tip as a control so I would have velocity data under the same conditions, even though I had chronoed that round from the same rifle previously. They were loaded to the exact same OAL as the factory rounds (which was also the OAL listed in the data used) in once fired Barnes brass, using a CCI small rifle magnum primer (which I also used for the sub loads).

Tested them using the bolt action. The factory rounds averaged 2394fps with a standard deviation of 23, and extreme spread of 56. The max load of 20.2 grains of W296 averaged 2437fps, with an SD of 6 and ES of 16. Since my goal is to replicate the factory load rather than exceed it, I will be loading the rest at the next step down of 19.7 grains, which averaged 2407fps with an SD of 7 and ES of 17. The step down after that averaged 2378 and had much worse SD and ES, same for the two lowest charges I used. This is consistent with what I have read about H110/W296, that it is happiest when loaded at or near max levels.

I did have a couple of primers in the supersonic loads that required multiple strikes, and I suspect these are the same ones I had difficulty seating in the brass (I think I have that issue resolved now). I didn't have that problem with any of the sub loads using any of the rifles and the same primers, so I am not going to worry about it for now.

All charges were individually weighed using an RCBS Chargemaster electronic scale and powder dispenser, and loaded on a Forster Co-Ax single stage press. My plan is to eventually acquire a Dillon XL650 which will be used for loading the subs (and lots of other things of course), but I will probably stick with the current equipment for at least the black tip hunting ammo due to the high precision that can be obtained that way.
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HTRN
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Re: Chrony of Truth

Post by HTRN »

Midway has the Lapua's and 220 match kings very closed in price, around .44 each. Have you tried Berry's plated 220s? They're like half the price.

BTW, if you ever see Berger 230 hybrid targets on sale, let me know. The damn things are over 60 cents a pop even in 250 count boxes. :(
HTRN, I would tell you that you are an evil fucker, but you probably get that a lot ~ Netpackrat

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Netpackrat
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Re: Chrony of Truth

Post by Netpackrat »

There was no point in trying the plated bullets because Grafs had the Lapuas for the same price.

Also Midway can eat a bag of dicks.
Cognosce teipsum et disce pati

"People come and go in our lives, especially the online ones. Some leave a fond memory, and some a bad taste." -Aesop
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Combat Controller
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Re: Chrony of Truth

Post by Combat Controller »

Netpackrat wrote: Sun Jul 07, 2019 3:59 am There was no point in trying the plated bullets because Grafs had the Lapuas for the same price.

Also Midway can eat a bag of dicks.
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Netpackrat
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Re: Chrony of Truth

Post by Netpackrat »

Combat Controller wrote: Sun Jul 14, 2019 2:29 pm
Netpackrat wrote: Sun Jul 07, 2019 3:59 am There was no point in trying the plated bullets because Grafs had the Lapuas for the same price.

Also Midway can eat a bag of dicks.
Tell us how you really feel!
Sure. Their shipping policy now consists of "Fuck you for living in Alaska." Rather than try to charge what shipping actually costs, now they charge you their regular rate plus an "Alaska" charge on top of that, even though they ship USPS and most stuff will fit into a flat rate box that costs the same to anywhere. Last time I ordered from them was the B&C stock for my .300blk bolt action, which I could have gotten from either them or Brownells. Went with Midway and paid the extra fee since they showed it as being in stock. Might as well have gone with Brownells since Midway pocketed the extra charges and shipped it slow boat; it took about a month to get to me. I don't like being charged extra for extra shitty service and I have not ordered anything from them since.
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Combat Controller
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Re: Chrony of Truth

Post by Combat Controller »

Fuck that shit.
Winner of the prestigious Автомат Калашникова образца 1947 года award for excellence in rural travel.
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Netpackrat
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Re: Chrony of Truth 300 Blackout Edition

Post by Netpackrat »

Netpackrat wrote: Mon Aug 13, 2018 9:26 amUMC 120 L300AAC1
AVG 2154 FPS
So FWIW, I bought some of this ammo packaged in buckets over the summer, and to my dismay, I found that it was loaded in R-P (Remington-Peters) cases instead of the Barnes cases that it was previously. For anyone who doesn't remember, this ammo came about as a replacement for the old 115 grain UMC load that was discontinued, and it ended up being a lot better than you might normally expect from el-cheapo Remington UMC. Because Freedom Group, the UMC 120 was actually loaded by Barnes using Barnes components (and shipped in UMC packaging), with presumably greater care than Remington normally puts into their lower priced line of ammunition.

In general, if your .300blk rifle didn't shoot this load reasonably accurately, then there was probably something wrong with your rifle. So I was interested to see if the ammo performed any different since at least the case headstamp had changed. Finally got to the range with it this afternoon, and while I didn't chronograph anything, I am pleased to report that using my 16" Model 7 bolt action with Saker can installed, I saw zero difference on the target between the older UMC 120 loaded in Barnes cases, and the more recently purchased version of the same load in the R-P cases. Same group size, same exact point of impact. So whatever else may have changed, it looks like the quality has not.
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Netpackrat
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Re: Chrony of Truth

Post by Netpackrat »

Another thing I had not previously noticed, is the newer version of the load does not have crimped primers, which Barnes at some point started doing, apparently to all of their 300blk ammunition. So one less hassle to deal with when reloading the brass.
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"People come and go in our lives, especially the online ones. Some leave a fond memory, and some a bad taste." -Aesop
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HTRN
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Re: Chrony of Truth

Post by HTRN »

Id be willing to bet that its essentially unchanged, just a different headstamp on the brass.
HTRN, I would tell you that you are an evil fucker, but you probably get that a lot ~ Netpackrat

Describing what HTRN does as "antics" is like describing the wreck of the Titanic as "a minor boating incident" ~ First Shirt
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