DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!

More
10 years 7 months ago #36183 by LebbenB
Replied by LebbenB on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!

Some say Nosler 77gn is better but these opinions are mixed on accuracy

I've been using Nosler Custom Competition bullets for some time now. They compare favorably to Sierra in accuracy, IMO.

Please Log in or Create an account to join the conversation.

More
10 years 7 months ago #36193 by SOC
Replied by SOC on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!
I think I have settled on an initial load for my MK262 "MOD3"

24.2gn 8208

Will load.

15 with a LFC crimp that is firm but not enough to distort the bullet.

15 without crimp.

My software will record 10 traces at a time.

10 traces no crimp.

10 crimped.

5 "extra" of each if I get a fail to read.

If it all goes perfect then I'll fire 5 of each on the same 10 round string.

Please Log in or Create an account to join the conversation.

More
10 years 7 months ago #36217 by MrMarty51
Replied by MrMarty51 on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!
I do`nt remember when or where I got this from calculator from. May have even been in here.
I was checking out My Remington 1917 Enfield, figured the twist rate, then got into the calculator and started working with velocities.
This is for a 30-06 cal bolt rifle. I do`nt remember what velocities is recommended for the M1 Garand so when I do begin loading I would like to load everything the same, for both bolt action rifles plus the Garand, if that would be possible and still retain a great degree of accuracy.
So, how would this calculator fit in with what You are doing with Your pressure testing ???
This guy is also asking if anyone has any specific bullet lengths then please email them to Him and He will add them into the bullet lengths chart.
www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

Please Log in or Create an account to join the conversation.

More
10 years 7 months ago #36218 by MrMarty51
Replied by MrMarty51 on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!
Will You be working on the .308 and the 30-06 configurations ??? or have You already done those ???
If so, and We would send You Our brass, is it better that We have it all cleaned and ready for final inspection before sending it on to You ???

Please Log in or Create an account to join the conversation.

More
10 years 7 months ago #36278 by SOC
Replied by SOC on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!

MrMarty51 wrote: Will You be working on the .308 and the 30-06 configurations ??? or have You already done those ???
If so, and We would send You Our brass, is it better that We have it all cleaned and ready for final inspection before sending it on to You ???


Will be getting 6 more strain gages soon.

Next up will be,

300 RSAUM
308 on my 16" carbine
308 on my Ishapore Enfield
454 Casual on my Puma 92
12gan on my repro 1887

The 6th gage is up for grabs but I hope to have either a Finnish M39 in 7.62x54R or Pre 64 Mod 70 in 30-06 ta apply it to.

No need to do any cleaning or processing of your brass unless you want to trim and size it to your particular rifle.
The following user(s) said Thank You: MrMarty51

Please Log in or Create an account to join the conversation.

More
10 years 7 months ago #36535 by SOC
Replied by SOC on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!
Final results.

10 shot string MK262 MOD3 with No Crimp

This image is hidden for guests.
Please log in or register to see it.



10 shot string MK262 MOD3 with Firm LFC Crimp

This image is hidden for guests.
Please log in or register to see it.


Berger Tactical bullets have a heavier jacket than other Bergers and the SMK, I was able to apply a lot of crimp using LFC dies without distorting the bullets.

I wanted to see how much crimp would effect the pressures and velocities of the load, so I applied as much crimp as I could without the common signs that it was excessive.

If I felt the need to crimp this load or someone wanted it crimped I would use about 1/2 the pressure I used in crimping this test load.

Final pic 1-5 are non crimped 6-10 are crimped.

This image is hidden for guests.
Please log in or register to see it.



A couple things interesting about the 5 and 5 test.

Judging just on velocity the 10 rounds of 5 each showed the best consistency in all arias, lowest SD, MAD, and ES of the 10 shot strings.

However on the strain gage it shows two curves that don't fit the others, they show sign of slightly delayed ignition and one shows lower pressure.

The end result of the two that don't fit is about .03 and .07 respectively of a millisecond more time in the barrel and 4 - 22 fps off from the averaged velocity.

It gives an interesting perspective on what a strain gage can tell you that a chrono can't.
The following user(s) said Thank You: jtallen83, Libertarian623

Please Log in or Create an account to join the conversation.

More
10 years 6 months ago #37849 by jtallen83
Replied by jtallen83 on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!
Shot 10 of my 100 clone reloads from SOC this morning, I'd have shot them all if my scope would have mounted up!
They functioned fine in my PM400 and all landed in a 12 inch circle on steel at 200 yards with iron sights, just a bipod, no rear bag and no lollygagging around, just sent them as quick as the sights got back on target :dance:
I can't wait to get these on some paper when I get the scope mounted up, maybe next weekend :pray:
The following user(s) said Thank You: Libertarian623

Please Log in or Create an account to join the conversation.

More
10 years 6 months ago #38288 by jtallen83
Replied by jtallen83 on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!
Finally got the new scope mounted on the PM400 so I thought I'd post some target results with SOC's MK262, the good ones of course!

This image is hidden for guests.
Please log in or register to see it.

Best 50 yard group,

This image is hidden for guests.
Please log in or register to see it.

best 100 yard group,

This image is hidden for guests.
Please log in or register to see it.

10 rounds on a 12-14 inch painted on steel target at 200 yards.
These are all with a stock pistol AR with a 10 inch barrel using nothing but a bipod for a rest and my usual fast as I can pace.
I'll be back to the well for another batch of these, well done SOC :clap: :usa:

Please Log in or Create an account to join the conversation.

More
10 years 6 months ago #38297 by Siscowet
Replied by Siscowet on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!
Nice shooting and nice job on the reloads SOC.

Please Log in or Create an account to join the conversation.

More
10 years 6 months ago #38310 by SOC
Replied by SOC on topic DANGER EXPERIMENTAL MK262 DUPLICATION BY SOC!!!
Glad to see your happy with the results.

I'm curious if your other targets showed vertical stringing as seen posted and if you feel it may have been due to where you paused your breathing to fire. You obviously have very good trigger control with as little lateral dispersion as seen on those targets.

How was flash and concussion? I don't have an SBR to test in but in my 16" I didn't really notice anything that seemed excessive.

Much of the newer ammunition the military is developing is using extruded powders with calcium carbonate as a flash suppressant.

Next up I have been researching the Navy R and D in developing an improved M118LR round they call the MK316. (Apparently they want less thermal deviation and more accuracy)

MK 316 MOD 0
175gn SMK
Federal Match Case
FGMM primer
41.8gn IMR 4064

I'm testing my own version with a couple changes as I'm unable to source FGMM primers or IMR 4064

I'm using 42gn of 8208 (175gn bullets are the upper limit for this powder in 308/7.62 and gives me some concern) and CCI 200 primers for initial testing but will copy exact once I can source a quantity of 4064 and FGMM primers.

Pressure testing matched with velocity will be from my 16" AR-10 Carbine. If pressures are within spec I'll load some in my Ishapore Enfield 308 to get an idea of what 25" barreled velocities are.

I hope to get 2450-2500fps from the 16" and 2725-2775fps from the 25" Enfield. (If pressures are good)

Also I'm up for any ideas on what ammo I should try to duplicate next, or even someones idea of a new (wonder round) hand load they would like actual pressure testing on.

As for my own project, I just ordered some of the new Berger 30 cal 230gn Hybrid OTM TAC bullets that have come out since Brian Litz started working with Berger bullets. Durn things have a G7 BC of .368, and a G1 BC of .719 as tested by Litz.

For a sense of scale the Armys new fangled XM2010 with the MK 248 MOD 1 (that was pulled for blowing primers in desert heat) is supersonic to 1590yds when adjusted for atmospherics at my altitude with the 220gn SMK at 2850fps at the muzzle.

I punched the Berger 230 into my ballistic calculator. If I can get a muzzle velocity of 2700fps from my AR-10TU it is predicted to drop sub sonic at 1750yds at my altitude of 3200ft.

I'm already pushing the 210gn Berger to 2900fps but my brass life is shorter than I like.
The following user(s) said Thank You: jtallen83

Please Log in or Create an account to join the conversation.