Sleuthing IMI 5.56 77gr OTM LR Mod 1 ??

My friend and I were both shooting this ammo last weekend out to 800yds. We have the same uppers with WOA 16" SS Match 1:7 barrels. We were banging a 12" steel plate at 800 yds pretty consistently with 8.5mils of adjustment and I shot a 5 shot group at 500yds that was just under 5". We chrono this ammo and got the following numbers:

Low (Cold bore) - 2645
High - 2721
Average - 2672
SD - 76


I wanted to make a handload that was extremely accurate and had similar velocity as the above noted IMI ammo. Here's what I made and tested today. It shot extremely accurate at 100yds which I also chrono.

1xLC
77smk
CCI 400
23.5gr 8208 xbr
COAL 2.2595"

Low - 2539
High - 2569
Average - 2556
ES - 30
SD - 13

I am extremely happy with the accuracy of this handload as 5 shot groups were around .5" with 4 of the 5 shots being around .36".

My only issue is with how much slower this load is compared to the IMI factory ammo. I am concerned because I want that additional 100+fps for shooting at distance.


Is anyone handloading 77smk or 77gr Berger OTM that are getting extreme accuracy and velocities in the 2650-2700 range like the IMI 5.56 77gr OTM ammo?? If so can you share your formula?

I have 8208xbr, 4064 and Varget but have only tested the 8208xbr with 77gr smk so far.

 
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Tx_Flyboy

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Don't sleuth anything.

Load 24.7gr Varget under 77smk and shoot it. Should get you close to 2,750 - 2,800ft/s from a 20" AR-15 and will be accurate than you.
 
Don't sleuth anything.

Load 24.7gr Varget under 77smk and shoot it. Should get you close to 2,750 - 2,800ft/s from a 20" AR-15 and will be accurate than you.

I wasn't going to sleuth anything, probably not the right word to use. I'm simply looking for a load that mimics or exceeds the IMI load's velocity but has the same sub half moa accuracy as my 8208xbr load.

Thanks for the heads up. I will try the suggested Varget load. Are you loading it to 2.260?
 
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07yzryder

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man berger WAY under states their loads. they have a max load of 22.5 but multiple sources have been running closer to 25 with no pressure loaded to mag length. Might have to load these up and see hwo the run in my rifle.
 

turtlesniper

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Ramshot tac at 5.56 pressure max of 24.8 gr by what there data says( i use 24.7)
2.245 oal
A medium crimp ( this is important to get pressure up)

2810 average ( drop confirmed)out of a 18 white oak spr barrel
 

GhostFace

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    I say all the time when these threads come up....AA2520 will give you higher velocities and great accuracy over Varget and JUST about anything else. ..
     

    1SMALLJOHNSON

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    My partnership is importing Explosia propellants from the Czech Republic. Just yesterday, I tested propellant type "D073-06" against Varget. The test load was a 175 grain .308. The Varget yielded a velocity SD of 14.4 with weighed charges. The D073-06 yielded a velocity SD of 11.3 with THROWN volumetric charges. Point being, there ARE alternatives to Varget out there.

    Back to getting on-topic: I have shot D073-06 with a 77 grain .223 load. It appears that 25 grains is a good, accurate load. Presently, I have no velocity or pressure data for that weight.

    In the background: This propellant is available to BATF class 6 loaders only, at the present time. We will move forward with canister "4.1, Flammable Solids" approval, where we'll be able to distribute it through the normal trade channels. I wish we were presently able to offer it to the public, but we've got to follow US DOT laws for transportation.
     

    Tx_Flyboy

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    07yzryder,

    I don't know much about the 77gr Berger OTM...but i suspect it's probably seating-depth sensitive unlike all their non-hybrid offerings.

    Measure the throat to your rifling. If you are circa 30-35-thousands off the lands at mag-length, then yes, that load should shoot lights out for ya.
     
    My partnership is importing Explosia propellants from the Czech Republic. Just yesterday, I tested propellant type "D073-06" against Varget. The test load was a 175 grain .308. The Varget yielded a velocity SD of 14.4 with weighed charges. The D073-06 yielded a velocity SD of 11.3 with THROWN volumetric charges. Point being, there ARE alternatives to Varget out there.

    Back to getting on-topic: I have shot D073-06 with a 77 grain .223 load. It appears that 25 grains is a good, accurate load. Presently, I have no velocity or pressure data for that weight.

    In the background: This propellant is available to BATF class 6 loaders only, at the present time. We will move forward with canister "4.1, Flammable Solids" approval, where we'll be able to distribute it through the normal trade channels. I wish we were presently able to offer it to the public, but we've got to follow US DOT laws for transportation.

    This deserved its own thread and provides no assistance or help to my original post/request.
     

    steve123

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    Look to the Berger 70 gr VLD target. About the same BC as the 77 grainer but can be driven 100 + fps faster.

    If you aren't concerned about brass life you can get away with hotter loads. I used to do this with 75 grainers but the brass only lasted 3 firings/2730 fps out of a 15" barrel with H-4895. This particular load was very accurate which is why I used it. BTW H-4895 is one of the best powders for shorter barrels as far as getting outright velocity and not being temp sensitive.

    Google ladder test. It won't take you but 20 rounds to determine where the nodes are.
     
    I perform OCW instead of ladder testing because Ladder is supposed to be done at 200-300 yds. Im limited to my local 100yd range. I have to drive 2 hours each way to shoot any farther.

    Ive heard good things about 4895 for .308, will get some and try in my 5.56 as well.
     

    steve123

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    I say all the time when these threads come up....AA2520 will give you higher velocities and great accuracy over Varget and JUST about anything else. ..

    Did you know that AA2520 is horrible temp sensitive? 100+ fps difference with 60 degree spread of temperature. 125 fps in the 6mmART40 I experimented with. It does meter nice though.
     

    bruddah

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    I was getting over 2,600 FPS using 77gr SMKs over 22.9 gr of IMR 8208 XBR in 1X fired PMC "HotShot" brass and CCI 400 primers seated to mag length which was generally longer than the stated 2.260" by about .008" - .010". Accuracy was excellent, getting under 1/2" groups @ 100 yds out of an 18" BHW barrel.
     
    Ok, I just got back from testing 8208 xbr and Varget. Here's the results

    All tests done with 77smk, 1xLC fully prepped and annealed brass and CCI 400 primers

    8208xbr 23.5gr
    COAL 2.248
    2591fps - ES 45 - SD 16

    8208xbr 23.8gr
    COAL 2.248
    2603fps - ES 41 - SD 14

    Varget 24.5gr
    COAL 2.2595
    2514fps - ES 52 - SD 20

    Varget 24.7gr
    COAL 2.2595
    2537fps - ES 49 - SD 17

    COAL for the varget load is wrong in the below picture. It should read 2.2595


    Varget is out for me as the above numbers are just too low and I was getting crunching when seating those loads to 2.259 - 2.260 showing signs of compressed load. So far 23.8gr of 8208xbr with 2.248 coal is my best load with highest velocity. I am not seeing any pressure signs so I'm going to work up in .2gr increments to see where that takes me. I have 8# of 4064 that I might try and I picked up 1# of 4895 today to test.

    Is my velocity issues due to not applying a crimp? Maybe the IMI factory loads are crimped. I am using a Forster Benchrest seating die that doesn't crimp. I am going to look to buy a .223 crimping die to test with.
     
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    GhostFace

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    I developed the load in the summer so I have no issues with it. I get 2835 fps out of an 18 inch barrel and submoa accuracy out 300 yards, that's the furthest I shot the load on paper.
     
    I developed the load in the summer so I have no issues with it. I get 2835 fps out of an 18 inch barrel and submoa accuracy out 300 yards, that's the furthest I shot the load on paper.

    The reason I don't want to use any temp sensitive powders is because its 70F outside right now while Im working up these loads. I will be shooting the load I settle on in a month when day temps will be in the high 40's to low 50's.
     

    dauntedfuture

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    Reference the comment about Berger 77's; they are not VLD bullets and are designed to be loaded to magazine length.
     

    1SMALLJOHNSON

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    This deserved its own thread and provides no assistance or help to my original post/request.

    Fair point. I'll put the load together and shoot it through a 16 inch barrel.

    Velocity at 15 feet, and accuracy at 100 yards?

    I don't have any IMI 77 gr OTM rounds. Would you prefer an alternative reference round or reference propellant?
     

    TheGerman

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    Ok, I just got back from testing 8208 xbr and Varget. Here's the results

    All tests done with 77smk, 1xLC fully prepped and annealed brass and CCI 400 primers

    8208xbr 23.5gr
    COAL 2.248
    2591fps - ES 45 - SD 16

    8208xbr 23.8gr
    COAL 2.248
    2603fps - ES 41 - SD 14

    Varget 24.5gr
    COAL 2.2595
    2514fps - ES 52 - SD 20

    Varget 24.7gr
    COAL 2.2595
    2537fps - ES 49 - SD 17

    COAL for the varget load is wrong in the below picture. It should read 2.2595


    Varget is out for me as the above numbers are just too low and I was getting crunching when seating those loads to 2.259 - 2.260 showing signs of compressed load. So far 23.8gr of 8208xbr with 2.248 coal is my best load with highest velocity. I am not seeing any pressure signs so I'm going to work up in .2gr increments to see where that takes me. I have 8# of 4064 that I might try and I picked up 1# of 4895 today to test.

    Is my velocity issues due to not applying a crimp? Maybe the IMI factory loads are crimped. I am using a Forster Benchrest seating die that doesn't crimp. I am going to look to buy a .223 crimping die to test with.

    Was literally loading 77 grain Nosler's last night and was trying varget for the first time in them and started to notice the crunch at 23.8 grains.

    Question, is this unsafe? I would assume its a compressed load and that's all but it has me wondering why you then seated these bullets further out to allow for more case capacity or was it because the bullet actually didn't have enough room at loadings higher than where I was just getting the crunch?
     

    918v

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    23.8grs of 8208 with RP 7.5's gives me 2650 FPS with .5-.7" groups and 9-15 SD out of my Noveske 16" barrel. I tried all sorts of primers and found 7.5's to be the most forgiving in terms of pressure/velocity. The brass lasts at least 5 reloads, but the primer pockets do loosen up a bit. It is hot. QL predicts 58,000 PSI.

    I've been playing with Russian primers as well but they like a lower charge weight with less velocity.
     
    23.8grs of 8208 with RP 7.5's gives me 2650 FPS with .5-.7" groups and 9-15 SD out of my Noveske 16" barrel. I tried all sorts of primers and found 7.5's to be the most forgiving in terms of pressure/velocity. The brass lasts at least 5 reloads, but the primer pockets do loosen up a bit. It is hot. QL predicts 58,000 PSI.

    I've been playing with Russian primers as well but they like a lower charge weight with less velocity.
    Whats your coal? Are you applying a crimp?

    I might try BR4 primers instead of 400's and see if that does anything.
     

    918v

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    It won't. The only difference is the primer cup is harder.

    I use 2.250" OAL. The question about crimp is interesting. I chronoed 23.2grs at 2560 FPS using a smooth 77SMK a couple weeks ago. Yesterday I chronoed a cannelured and crimped 77SMK with 23.4grs and got 2611 FPS. This is with the Tula 556M primer. It seems the crimp adds a little speed, I'd say 20 FPS. It certainly does shift the POI to the left by half an inch.
     
    Ok, I worked up three new loads last night with increasing charge weight to see how high I could get velocity before seeing any pressure signs. I took the below loads to the range this morning to test them out. I didn't seat the bullets as deep as the last test rounds due to increased charge weight this time as I wanted to see if there were any pressure signs. Here's this morning's results. There were no pressure signs at all with any of the below charges and 24.4 is showing good velocity.

    Again all in 1xLC fully prepped brass using 8208 xbr, 77smk with CCI 400 primers.

    23.8gr - Sighter Rounds
    1.8505 ogive
    2588fps - ES 25 - SD 10

    23.8gr
    1.8520 ogive
    2589fps - ES 60 - SD 23

    24.0gr
    1.8540 ogive
    2603fps - ES 25 - SD 12

    24.2gr
    1.8540 ogive
    2620fps - ES 31 - SD 12

    24.4gr
    1.8540 ogive
    2667fps - ES 32 - SD 13


     
    After shooting the above loads this morning I came back home and worked up 3 more loads all using 24.4gr but tested different seating depths. The results were excellent. Velocity is right around where I wanted to be and ES/SD numbers look great. The last group all the way to the right was the best, 4 of those shots are right at .50", I pulled the 5th and knew it instantly. I was rushing because I had my son with me this time who was hungry and wanted to go. I am going to load 20rds using the last load and shoot 4 groups and see how it does. I may try going to 24.6 and 24.8 to see if I get any pressure signs as I'm not seeing any so far, primers and cases look great.

    24.4gr
    1.8485 ogive
    2666fps - ES 16 - SD 7

    24.4gr
    1.8510 ogive
    2663fps - ES 5 - SD 2

    24.4gr
    1.8530 ogive
    2665fps - ES 16 - SD 7


     

    OF&B

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    I'm in the honeymoon phase with my Magnetospeed. These are some pressure/velocity ladders I shot last week. The actual velocities were fit to a line to clean them up.

    Old 24" DPMS 1:9 barrel. 2.260" OAL, 2.280" to the lands with the 77 smk. Depending on the powder, ~2850 fps seemed to be 223 max pressure, 2925 fps for 556. Might get 3-4 loading at 2850, one and done at 2925. With a 16" barrel Quickload gives 2610 and 2680 fps for the limits.

    I've used the 24.5 grain Varget load with Remington 7.5 primers for a few years and it works well. It looks like H4895 is going to give more velocity without a compressed load. BLC2 was the tamest for a given velocity by far. I was surprised at the pressure/velocity differences between the primers.
     

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    Stpilot12

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    Great thread guys.. Keep it coming! I've been playing around with 69smk's but Ive been wanting to jump on the 77 bandwagon next. Picked up some 8208 today. Thanks for the intel.
     

    MCSO1357

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    I'm definitely interested in H4895 load results


    Sent from my iPad using Tapatalk
     
    I just loaded up 20rds of my best 8208xbr to confirm accuracy and chrono numbers are consistent before making it my final load. I also loaded up 5 shots each of H4895 23.3, 23.5 and 23.7. From all the .223/5.56 load threads I've read it appears right around 23.5 everyone is finding a node. I will test both loads tomorrow and report back.

     
    I shot 20rds through the chrono this morning with the following load.

    8208xbr 24.4gr
    1xLC
    77smk
    CCI 400
    1.8530 ogive

    2672 / ES 21 / SD 8

    I also shot 3 groups of H4895 seated to 1.8570 Ogive using 23.3g, 23.5g and 23.7g

    23.3 was scattered, 23.5 was very accurate and 23.7 was vertical stringing

    Unfortunetly my chrono wasn't reset so I didn't get numbers for the 23.3 and 23.5 loads but I did catch it and get 23.7. Its a tad slow but acceptable. I suspect 23.5 is right around 2600fps. I will make up some more 23.5 loads and test seating depth and get chrono numbers tomorrow morning.

    23.7gr 2614fps / ES 31 / SD 12

     
    I tested H4895 today with different seating depths. It was extremely windy outside and I pulled the 5th shot on the 1.8600 group but results looked good. Velocity is about 90fp slower than my hot 8208xbr load but this H4895 load is very accurate.

    1xLC
    H4895 23.5gr
    77smk
    CCI 400
    1.8585-1.8600 Ogive

     

    Stpilot12

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    So, I thought I post this here since I followed your info. Thank you for posting all this, you probably saved me a few primers and a bunch of powder. Anyway, here's what I got on my initial OCW with 77smk and 8208.

    I was initially going to run 23.4 to 24.2, but I bailed on 24.2 due to flat primers at 24.0.

    Data:
    LC06 1x annealed, weighed to within .5gr
    Fed 205M's
    8208XBR
    77SMK's weighed to exactly 77.0
    Seated to 1.853 Ogive
    No chrono…:mad:

    Rifle:
    Black Rain w/18" WOA 1/7 SPR mag fed, shot round robin

    3 each, 23.4, 23.6, 23.8, 24.0

    Top row only
    IMG_1493.jpgIMG_1494.jpg

    I know they're only 3rds, but the last 3 groups all measure .5 with 24.0 being .41
    I wish I knew the speed!!! Anyway, I think I'm gonna load up 5 of each, 23.8-23.9-24.0 and try again. I may be able to borrow a buddies chrono on Wednesday(i hope)
     
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