77 grain SMKs for 600 yards?

[tflorman]

I tried some RDFs once and had the flyer problem, I may pick another powder and see how they do. I am also ordering some 80 ELDs to try

I just bought 1000 of the 77 RDFs blems from shooter's pro shop and didn't have much luck at a mag length load... one rifle liked 22.6 grains of IMR 8208 in wolf brass, but the other rifle preferred 23.4 which was a tad too hot. Im not sure of the MV because I didn't have a chrony set up, but my shotmarker target put the speed at 2340 FPS at 200 yards for the 22.6 grain load, and 2412 for the 23.4 grain load shot out of the other rifle.

What i found was that you have to load them longer to get them to group without the flyers. For my rifles with Wylde chambers, it either liked .010 off the lands (1.950ish CBTO with the hornady OAL comparator) or .050 to .060 (1.900 CBTO) off the lands. I also had some 70 RDF bullets and found these COAL's to work for that bullet as well (must be the ogive shape that determines this). Mag length simply didn't work as well. If you go with these bullets, I recommend finding a safe powder charge for whichever powder you go with, then play with the COAL. If it has to be mag length, other bullets will probably perform better, but if you're developing a 600 yard load, these 77 RDF's undoubtedly have a pretty high BC (I'm guessing .450ish given their length and point shape using a the .416 BC of the 70 RDF as a guide).

The photo below illustrates what one of my rifles did with the mag length loads, the other rifle with the newer barrel didn't do as well. You can see the powder charges which name each group. As I mentioned the 22.6 load worked well but the bullet isn't moving as fast as I would like for a 600 yard load and I already have a nice 62 grainer load for the short lines where bullets cost far less.

 

[GSS]

I have had Great Results with the 77 Grain SMK's @ 2.260" COAL(works fine in USGI 20 rd. Magazines). .

Minor note from experience;
Bullets from all manufactures vary from base to tip / ogive to tip to varying degrees.

If you are shooting rapid fire XTC stages much better to set your Avg COL to 2.250
Alibi's are no fun for anyone and best to be avoided if at all possible.

 

[GSS]

I have had Great Results with the 77 Grain SMK's @ 2.260" COAL(works fine in USGI 20 rd. Magazines). I have been using Pulled Bullets when available.

Muzzle Velocities @ approx. 75' Elevation with 23.4 Grains IMR XBR-8208 & TULA Primers in Lake City Brass.

16"=2532@ 70*F BP=29.95 Humidity=74% 1/8 Twist

These are pretty hot.
Depending on Temperatures I sometimes see Ejector Marks/Swipes. 5.56 NATO & .223 WYLDE Chambers ONLY!!!

Backdown the powder charge 5-10% and work it back up from there.

I Love this load out to 600 yds. It's worked great for learning to read wind. YMMV.

Pardon the edit on your posts.
I have been hoping to see someone that tried 77's in a 16" barrel from 600 yards.

Do these bullets stay stable at target from 600 and capable of holding the aiming black for 100% of the well aimed shots?

Or are they struggling at 600 to hold paper?

Anxious to hear, Thank You

 

[r bose]

I just bought 1000 of the 77 RDFs blems from shooter's pro shop and didn't have much luck at a mag length load... one rifle liked 22.6 grains of IMR 8208 in wolf brass, but the other rifle preferred 23.4 which was a tad too hot. Im not sure of the MV because I didn't have a chrony set up, but my shotmarker target put the speed at 2340 FPS at 200 yards for the 22.6 grain load, and 2412 for the 23.4 grain load shot out of the other rifle.

What i found was that you have to load them longer to get them to group without the flyers. For my rifles with Wylde chambers, it either liked .010 off the lands (1.950ish CBTO with the hornady OAL comparator) or .050 to .060 (1.900 CBTO) off the lands. I also had some 70 RDF bullets and found these COAL's to work for that bullet as well (must be the ogive shape that determines this). Mag length simply didn't work as well. If you go with these bullets, I recommend finding a safe powder charge for whichever powder you go with, then play with the COAL. If it has to be mag length, other bullets will probably perform better, but if you're developing a 600 yard load, these 77 RDF's undoubtedly have a pretty high BC (I'm guessing .450ish given their length and point shape using a the .416 BC of the 70 RDF as a guide).

View attachment 1089050

What I found is the 77 RDF's are longer than some 80g bullets (sierra and nosler for sure) and have the typical VLD shape, short bearing surface. My service rifles have a 7 twist barrel. I was fortunate to get good speed and honest 3/4 min 200 yd groups loading mag length. Kinda kicking myself for not buying a few 85 RDF's to try loaded long at 600. Off topic but I shoot 105 6mm RDf and 140 6.5mm RDF and the y like to be spun. 8 twist is marginal at best.

 

[tflorman]

What I found is the 77 RDF's are longer than some 80g bullets (sierra and nosler for sure) and have the typical VLD shape, short bearing surface. My service rifles have a 7 twist barrel. I was fortunate to get good speed and honest 3/4 min 200 yd groups loading mag length. Kinda kicking myself for not buying a few 85 RDF's to try loaded long at 600. Off topic but I shoot 105 6mm RDf and 140 6.5mm RDF and the y like to be spun. 8 twist is marginal at best.

I figured the 85's were more meant for the 22 Nosler/valkyrie type barrels or specially throated 223 palma guns so I didn't bother with the 85's. I did hit the range today to verify my initial findings and was happy with the result. The following target is the 77 grain RDF, 23.2 grains of IMR 8208, loaded to 1.9 CBTO or about 2.350 COAL.

 

[Rtheurer]

According to what I’ve seen and they told me
All the bullets come out of the same box , commercially loaded ammo.
It’s amazing what little things like talent, amazing wind reading ability, and hard holding can do for your 600 ya scores.

Amazing what gets past around as truth. They have been shooting 75 VLD's the last Few years and 80gr Sierra's prior to that at 600 yards. The ammo is made at the Shop at Easley Range there at Ft Benning. Troy Lawton runs the shop, They have a staff of 3 plus Troy that custom load the 600 yard line ammo. Most of the big Military teams shoot hand load ammo at the 600 yard line and Factory ammo at 200 and 300 yard lines. It has changed over the years from Black Hills to Atlanta Arms and a few teams shooting MK262 LR ( Black Hills COmbat ammo) . Its been from the beginning that the AMU has shot custom ammo at the 600yd line since they switched to the MOuse gun from the M14.
Little bit of history and knowledge for you sir. Hope this finds you well.

 

[SG4247]

Pardon the edit on your posts.
I have been hoping to see someone that tried 77's in a 16" barrel from 600 yards.

Do these bullets stay stable at target from 600 and capable of holding the aiming black for 100% of the well aimed shots?

Or are they struggling at 600 to hold paper?

Anxious to hear, Thank You

My bbl is 18” .233 Wylde, custom made from a Wilson Arms SS blank.

I never chronied this load, with the 77 SMK and N540. But it is a compressed load at 2.250”.

 

[natdscott]

Hehehehe....

77 SMK fall from the sky at 599 yards.

 

[SG4247]

Ohh do they! I can see them coming in at a very high angle to the target with the spotting scope.

Arc em in there!

 

[Andy Legg]

Pardon the edit on your posts.
I have been hoping to see someone that tried 77's in a 16" barrel from 600 yards.

Do these bullets stay stable at target from 600 and capable of holding the aiming black for 100% of the well aimed shots?

Or are they struggling at 600 to hold paper?

Anxious to hear, Thank You

No Problem staying in the Black. I believe the wind call window would be +/- about 3 MPH to stay on in the black @ 600. Window for staying on target should be +/- around 6 MPH.

I have some of the 77 TMK's but haven't tried them just yet.....maybe before attending a State or Regional Meet.

 

[nastynatesfish]

I shoot 23.3gr of arcomp with the 77gr noslers. Out of a 20” oly barrel 1-8tw and I can keep half or just over 1/2moa at 610yards. I seat them at 2.235. I average 2805fps with them. I also shoot the cheap 75gr hornady at about the same speed and 1/2-5/8moa. I just finished load work and ran everything over a crony. 23.5gr shot a bit better but the es was about 25

 

[r bose]

I figured the 85's were more meant for the 22 Nosler/valkyrie type barrels or specially throated 223 palma guns so I didn't bother with the 85's. I did hit the range today to verify my initial findings and was happy with the result. The following target is the 77 grain RDF, 23.2 grains of IMR 8208, loaded to 1.9 CBTO or about 2.350 COAL.

View attachment 1089112

I'd take that group!! My groups aren't quite that tight at 300 yds mag length 77 RDF's but they'll clean the prone rapid target any day. I've had no problems shooting the 82 bergers so a 85 RDF, that I will probably jam in 20k because that's what I do with all VLD bullets, should shoot fine in a service rifle. Might turn out to be a good compromise between an 80 and a 90.

 

[Idaho-45]

Guys, I'm very interested in this!! I recently purchased a Rainier Arms Mod2 223 Wylde 18" 1-7.5 twist, barrel, & had it installed on an Aero Precision upper. Then, for better, or, worse, bought 500 Sierra 77 Matchkings. I'm currently trying to work up some decent loads for this AR Upper... So, please feel free to give us some more input on load data. I've been loading for years, & understand about reducing other people's loads for my personal weapon...... Just hoping to get a bit more input about powders for these bullets!!!!! Thanks in advance!!!!!! Idaho-45

 

[HomeSlice]

You'd need to push the 69SMK to 3000 fps to get close to the wind drift values of the 77SMK @2700. You cant push the 69 fast enough to beat the 80. That alone is reason enough for me.

 

[r bose]

Guys, I'm very interested in this!! I recently purchased a Rainier Arms Mod2 223 Wylde 18" 1-7.5 twist, barrel, & had it installed on an Aero Precision upper. Then, for better, or, worse, bought 500 Sierra 77 Matchkings. I'm currently trying to work up some decent loads for this AR Upper... So, please feel free to give us some more input on load data. I've been loading for years, & understand about reducing other people's loads for my personal weapon...... Just hoping to get a bit more input about powders for these bullets!!!!! Thanks in advance!!!!!! Idaho-45

Tried and true loads for mag length 77's used for decades in service rifle competition.

varget 24.0g
Rl-15 24.1g
h4895 23.5g
tac 23.5g
748 23.5g
aa-2520 24.2g
n-540 25.0g

and lately 2000mr 26-27g I'm currently at 26.6 getting a bit over 2800 FPS

 

[nhshooter]

anyone have a list like the above for the 69 grn sierras
tks

 

[Twdmar]

Amazing what gets past around as truth. They have been shooting 75 VLD's the last Few years and 80gr Sierra's prior to that at 600 yards. The ammo is made at the Shop at Easley Range there at Ft Benning. Troy Lawton runs the shop, They have a staff of 3 plus Troy that custom load the 600 yard line ammo. Most of the big Military teams shoot hand load ammo at the 600 yard line and Factory ammo at 200 and 300 yard lines. It has changed over the years from Black Hills to Atlanta Arms and a few teams shooting MK262 LR ( Black Hills COmbat ammo) . Its been from the beginning that the AMU has shot custom ammo at the 600yd line since they switched to the MOuse gun from the M14.
Little bit of history and knowledge for you sir. Hope this finds you well.

Are you still frosted from getting stuck in that scissor lift the other day Russ? Winter sucks right?
From my own experience, mag length 77s with 23.5 reloder-15 and rem 7&1/2 will almost clean the MR-1 target at 600, but that's with a 20 inch barrel. It's a mild, reliable load and accurate enough though i usually use the 80s.

 

[sveltri]

Fantastic results with 77 SMK at 600 loaded at 2.250” with N540.

YMMV

What kind of velocity is this load producing? Thanks

 

[Jeff Porter]

anyone have a list like the above for the 69 grn sierras
tks

Add about 0.5 gr to each of those for a 69. My two favorites are 23.8 of 8208 or 24.0 of H 4895.

 

[mace2364]

Not exactly an apples to apples comparison, but I personally have hit silhouette steel targets at 1000 yds with 77gr SMKs. I was using Black Hills ammo(I didn’t yet handload back then), out of a 20” rifle. It wasn’t a one shot thing either, I did it repeatedly. That was back in 07’ when 77gr were the new hotness(I remember this because it was not too long before my 3rd tour). Then years later I shot a PRS match with the same rifle, with some handloads using 77gr SMKs. There was a target at about 800, and I had a 1st round hit on it. I’m quite confident I could take that rifle out to 1000 again right now with 77gr SMKs.

In something a bit more relevant to what you’re wanting to do, I built a 20” service rifle in a class that John Hollinger put on out at Trinidad State 8-9 years or so ago. At that time, he said he used 77gr SMKs across the course. And I use them in the rifle I built in that class-though currently I’ve only shot it in steel target type matches(that’s all I’ve managed to get to recently). They are out to 600 though.

Anyway, I said all of that to say this: the bullet will do what you’re wanting to do with it.