OCW SMK 77 and CFE 223

[texasplinker]

Fortunately, central Kentucky weather was kind to me today and gave me a day with decent enough weather to run my first effort at an OCW exercise. It took longer to make the shots than I would have guessed. Also, shooting round robin seemed to make me focus on my form and consistency more than just shooting groups. Turns out both need work.

I loaded up charges every .2 grains of CFE under SMK 77 from min to .3 over max. Maybe I'd get there, maybe not. FC brass, CCI 400 Primers.

Barrel is a White Oak Armament 1:7 223 wyld. Glass is Bushnell Elite 3-12 mil model.

It was interesting to watch the groups develop. The first string looked like all charges below 24 were hitting middle of the grid and all charges 24 and above were hitting at the bottom of the grid. It didn't quite work out that way.

Looks like my accuracy node 24.2 - 24.4. This is just over published max of 24.1. I'm going to check out 24.1 - 24.4 in another workup. The primer were just barely starting to dimple back out at 24.6. On a warmer day it might become a concern. Any thoughts on how temps will effect this narrow window? It was mid 40s while shooting. It is curious to me that the hits moved down with pressure.

What are the chances I have to do this again in a few months when I hang a suppressor on this thing?

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This is 3 shots with 24.2, 24.4, 24.6. I I suspect the 24.6 is the low shot. I couldn't resolve the hits as they came. Overall, I am pleases with the initial results with CFE 223 and the SMK 77. The picture doesn't show it, but the index card was level when shot.

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This is 6" plate I used as a benchmark. 4 shots of re15 and SMK. Cold bore shot was good elevation, but I over compensated for the wind and missed. The next three are the three along the lower right side. ~3.5" CTC. The other hits were leftovers from the OCW. The 4" plate was with my 10/22 at 100 yds for kicks.

<a href="https://picasaweb.google.com/lh/photo/RzUBxVn7mPrG7LGxOL7TbQrFw8BRomtuXZljcak82vU?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/-DSGvIV8UsCw/UuXI9GdomlI/AAAAAAAAA-w/3BXai_MNKmM/s800/0126141959%257E2.jpg" height="450" width="800" /></a>

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<b>Tldr: Groups with the smk/cfe combo moved down as pressure increased. Pleased with initial results. Accuracy node 24.2 - 24.4. Round robin is hard. My form needs work. Is a suppressor going to require a new work up? </b>

 

[ChrisGarrett]

Nice shooting and write-up.

Can't help you with the suppressor, or the hot weather coming soon, but I would load up a box of 50 rounds and go 10 rds of 24.0grs, 10 rds of 24.2grs, 15 rds of 24.4grs and 15 rds of 24.6grs, shooting 5 shot groups at 100yds to see what you see.

Or any variation of the above.

Chris

 

[Henny]

I've noted when testing loads with a suppressor attached I'd get ejector marks sooner. This could possibly be from the over gas situation the suppressor causes. Without the suppressor, the ejector marks do not exist.

With my suppressor, (Surefire 556212) there has been minimal (.5 moa) impact shift with the loads I have tested.

How have your velocities and extreme spreads been with CFE? I was working with CFE and 77 SMKs and just wasn't getting satisfactory extreme spreads or velocity. My results with 24.0 gr is 2,501 FPS with an extreme spread of 54 FPS. This is with a 16" Colt, with suppressor attached. 54 fps is too high to be acceptable to me. I like the keep the ES below 25 fps. I shoot steel in 3 gun and for enjoyment out to 500 yards. A 50 fps ES will mean about a 1moa difference at 500 yards. Without even the loads accuracy, shooter ability and environment (wind, the adrenaline of competition and shooting against the clock, etc) you're already introducing a 1 moa error just due to the ammunition's ability.

This same rifle with the maximum load of 8208XBR (23.2 gr), Wolf small rifle magnum primer and 77 SMK, is pushing 2,650 fps, with an extreme spread of 21 fps. Interestling enough, just above and below 23.2 grains the ES went up to between 50 and 60 fps. Hmmmm... Note: I'm working with XBR now because Reloder 15 is pretty much non existent in my area! It's too bad too, because RE15 was my go to powder for 77 SMKs!

 

[pmclaine]

Thank you for the detailed write up. Im doing similar with CFE223, 8208XBR and TAC under 77 Nosler CC. My handicap right now has been shooting with BUIS while I wait for my scope from USO. Im not getting great data to work from with irons. Im just hoping to come up with some good cannon fodder ammo right now until I can do some testing usng a scope.

Between CFE and XBR I did see better results with the XBR. Maybe powder, maybe luck. I wish I had my scope to eliminate more of my errors.

What length barrel are you using? Im loading for a NATO/5.56 16 inch CL LMT barrel.

 

[peaceatwar]

Thanks for the write up! Do you have any velocities? ES/SD?

What length barrel?

I just got 2lbs myself to test! Going to test 77 SMK and 80.5 Berger FB

 

[texasplinker]

It is an 18" mid length.

I left the chrono at home. I have a bad habit of just loading to a pre determined velocity. I didn't want to think about it on my first try at ocw. Based on what I know of my re15/smk load the CFE is coming out about the same or just a bit faster. So right around 2700-2750. The re15/smk load clocked at 2733 at about 60°. At 300 yds the cfe poi was is just about the same as the re15 with with the same comeups.

Next time out I'll take the chrony and get a full velocity work up on a smaller charge window.


I'm researching the CFE because I can't find re15 anywhere either, what is the deal? If I can't get the CFE dialed in, I'll check out the xbr.

Pmclaine, I'd suspect that that you would have to be one hell of a shot with irons to make the difference in accuracy with those combos stand out. My worsr group was probably under 1.75" and the best was half that. Most were just over an inch. If you have a quality scope that lmt can borrow for a while, it might be worth it.

Thanks for the input y'all! I appreciate it!

 

[pmclaine]

Pmclaine, I'd suspect that that you would have to be one hell of a shot with irons to make the difference in accuracy with those combos stand out.

Yeah...that's not me.

As I'm loading right now Im making samples of ammo with a two grain spread of 5 shots each for 50 or 55 rounds. I went a little bit North of mid point on manufacturers recommended loads so that my highest charge is a grain or so above max. Im saving those for when my scope comes in. I haven't seen any signs of pressure on either my CFE or XBR loads when up to .2 above max but I am firing them in 30 degree weather.

I have 8 pounds of CFE and I think in the mean time I am going to make some ammo at +/- 23 grains to just keep me going. Some samples I made at the loading hold black on an SR target reduced for 100 yard use. My XBR loads held black at 200 yards on an SR target. They are good powders. I have been actively seeking RL15 since June with no luck to give it a try. Id like to load up the TAC to try but my reloading bench is now occupied building Pinewood Derby race cars.

I think XBR is pretty temperature stable so that shouldn't be an issue. To me the stuff looks and smells like mini Varget. Im loading on an S1050, trickling to desired weight. My low pulls have been coming out consistent enough that when I find a sweet spot load I hope to be able to go full progressive and a tenth or two either way wont matter.

I gave some good natured ribbing to USO today regards my scope. Ive been waiting a year for a 1-8X (SR8M). The wait has kind of sucked but I made out as Ive taken advantage of the time to upgrade my original order with some new features USO introduced for that scope. Ive been told maybe next month they will have everything to get my scope into production.


Good luck with your loading, please update regarding what you find out.