69gr SMK load development. What do I do now?

[MS50]

I've worked up a 69gr SMK load for my 12FCV 223. I used Win brass, CCI#400 primers, H335 24.4gr. .010 off the lands. Chrono avg via calculator is 3060fps. I don't have SD's because I didn't shoot groups but fired round robin with my loads. At 300yds the spread is 1.7in. Winds were 5-10 mph and shifting as they always do inside the berms. My question is should I attempt to achieve tighter groups with this load before I load a couple of boxes and get on with practice? I don't know what to expect with a 223 at this distance. I hope to use this rifle out to 600yds at some point, but my primary target rifle is a .308 10FP.

[GaCop]

You can always play with seating depths going into the rifling to see if that tightens things up. 1.7" is not bad at all at 300 yards. That's close to what I'm getting with my 223 AI using the same bullet. I'm loading with VV N-140 powder and jamming .008" yielding 1.4" at 300 yards when I'm on my game.

[homefrontsniper]

Maybe get some TMKS 69GR. Or some 77gr TMK and some Reloder 15/ 77gr.smk @ 2830 m.v.. Tac powder can get you at 2900 or more m.v with 77 smks . Whats yoir twist ? 1-9

[Robinhood]

I hear you homefront. Tha R 15 with the heavies is sweet. I would think a 1-8 or faster would be the sweet spot.

[MS50]

Thanks for the feedback. The 12FCV is a 1:9. Most of the information I've seen states that 69gr is about the max I can expect to consistently stabilize with a 1:9. I suppose if I worked with different powders, etc. I could attempt to use longer heavier bullets. That'll be a project for next fall. Thanks again.

[Jamie]

My Savage 1:9 would shoot 77 grn SMKs into small groups I don't think you will get much heavier than that through it though. Give some a try.

[homefrontsniper]

77 work in 1-9 twist.. you will not be sorry !

[jonbearman]

The 1 in 8 twist is more than adequate for the 69 grain matchking. You don't have to go faster.

[GaCop]

Thanks for the feedback. The 12FCV is a 1:9. Most of the information I've seen states that 69gr is about the max I can expect to consistently stabilize with a 1:9. I suppose if I worked with different powders, etc. I could attempt to use longer heavier bullets. That'll be a project for next fall. Thanks again. I load for my son's 223 with a factory 1 in 9 twist fluted SS varmint barrel. His rifle loves the 75 gr A-Max pushed by 23.3 grains of Varget. I seat the A-Max to the lands and get chronographed velocity of 2784 fps. The load groups into .615" at 100 yards. 1.7" at 300 yards and 2.4" at 400 yards. This load make short work of the club's steel pigs set up at the 300 yard line.

[scope eye]

77gr sierra's going 2800 fps out of a 9 twist is 225.000 RPM that is plenty rpm to stabilize them, "and not hard to attain" adjust your load powder load or seating depth.

Dean

[earl39]

77gr sierra's going 2800 fps out of a 9 twist is 225.000 RPM that is plenty rpm to stabilize them, "and not hard to attain" adjust your load powder load or seating depth.

Dean

Deano is correct. I use long range match which is pulldown power and basically RL-15 and get 3000fps with 77 MK's. No i won't tell the load cause it is above the book load but no flat primers or sticky bolt and fired brass will rechamber with ease so 2800 should be easy enough. One note, Mine is a 9 twist and punches nice round holes at a grand. I did drop points compared to the 308 but i belive i will be able to get them back as i learn the load and what the bullet will do at range.

[MS50]

I'm going to stick with the 69gr for now. There's not enough hours in the day to work up multiple bullet lengths. I hear what you are saying about the longer/heavier bullets. Thanks.

[Texas10]

Today I shot some 69 gr SMK over 25gr of TAC in my 9 twist model 12. Winds were 12 to 15 and gusty. Temp about 80F. I also shot some 50gr. Hornaday SP. These usually shoot pretty tight, but in todays wind my groups were all over the place, until I loaded up the SMK's. They didn't seem to care about the wind, and shot overlapping holes at 100 yds. It was amazing to see how, from one shot to the next, groups suddenly tightened right up with a heavier bullet.

Now, about those 77's…...

[homefrontsniper]

Today I shot some 69 gr SMK over 25gr of TAC in my 9 twist model 12. Winds were 12 to 15 and gusty. Temp about 80F. I also shot some 50gr. Hornaday SP. These usually shoot pretty tight, but in todays wind my groups were all over the place, until I loaded up the SMK's. They didn't seem to care about the wind, and shot overlapping holes at 100 yds. It was amazing to see how, from one shot to the next, groups suddenly tightened right up with a heavier bullet.

Now, about those 77's…...

Tac. And Reloder 15. Varget. Xbr8208 all GOOD for 69//77//80//90 !

[Texas10]

Tac. And Reloder 15. Varget. Xbr8208 all GOOD for 69//77//80//90 !

You bring to mind a question that has been bothering me for awhile now. In my Hornaday 9th addition reloading manual, the chapters for the 223 caliper are broken down into three sections; 223 Remington that lists charges for bullets up to 60 grain, 223 Remington Service Rifle (AR-15) Data listing 68 to 80 grain bullets, and lastly 5.56 mm Nato for 55 to 80 grain bullets. The manual is specific about NOT loading for 223 by using 5.56 data however, with regard to the 223 service rifle data, there's no mention of applicability nor warnings to using listed loads in 223 chambered rifles other than the AR-15.
So far I have been wary of using Hornaday manual load dated listed for Service Rifle in my model 12 in 233, but I have recently loaded some 69 grain bullets using Nosler and Sierra load info.
Other than the usual safety procedures of starting low and look for pressure signs while developing a new load, in your experience is the Hornaday Service Rifle Date applicable to the 223? Can I safely use this information to start load workup on heavier bullets? Interestingly, the data for the 75 and 80 grain bullets warns that a 1-8 twist or faster is required to stabilize those Hornaday bullets. Are other similar bullets made by other manufactures such as Nosler, Sierra, Barnes going to be better stabilized in my 1-9 twist? Or is that something I have to learn for myself through trial and error?

As always, your opinions and experience are much appreciated by this newby!

Still looking for the bottom of this rabbit hole I've fallen into…LOL

[scope eye]

If you want to pick up the pace on those 69gr Sierra's, get some CFE 223 you can load a full case, without signs of pressure and end up past 3200 FPS.

Dean

[CharlieNC]

If you maintain that group you can win many Ftr matches.

[MS50]

I fired the 69gr SMKs loaded with H335 yesterday. I was able to hit 7x12 steel at 650yds. The bad news is that I was blowing holes in the primers. The bolt was tight on extraction. I showed the brass to others there, and we also examined the bolt face, which showed no signs of damage. At first I thought it was a deep dimple, but it was a black hole. The Hodgdon site shows that the 24.4gr load is over max. The Lyman and Sierra references shows that it is well below max. I checked OAL and they're at 2.590. Chambered rounds showed no signs that they were into the lands. I'm back to the loading bench with the 69s. My workup started at 22.3gr H335. I saw no decent groups until I reached 24.4gr. Anyhow, it's a re-do on this work-up.

[jonbearman]

With the 69 grain sierra bullets you should be following the sierra manual as they have a more extensive listing of powders and bullets they make.