help finding a weak link in my hunt for accuracy?

flying pig

flying pig

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Hey guys. Took lots of advice that was given to me on here a few months ago right to heart. I've been working on my reloading gear set and my rifle as well as my shooting. I haven't had a lot of time, two young kids, wife, 85hr a week job and no daylight in evening have all hurt the search a bit but at least I am getting some shots down range and info logged.

First off I'm shooting a Savage M12 FCV in 223 (1 in 9 x 26" factory barrel), 5-15x40 elite tactical, I bedded it with devcon titanium a few months ago and the trigger is set as soft as it goes. I've been shooting prone from sandbags using a rear bag.

My load I'm using is 23.8gr of ramshot tac with 65gr Sierras. CCI primers, nosler brass. I've been neck sizing only. I haven't started turning necks yet, but I will. I have a mini lathe with a live center. I need time to get it tuned, its no where near centered the way I got it. I weigh every charge, even if it takes me 3 or 4 tries to be happy with 1 charge.

Reloading gear: I've been using the lee anniversary kit. I bought a redding trickler. I use rcbs dies.

I don't yet have a chrony.

The range: up to 620m, 6m of elevation drop (approx) over that distance.

Last time out I took 100rds with me. Started off by zeroing at 100m. Used my pick up odometer to find range (I know its not precision but I'm still working on my kit) and moved 100m at a time finding the bull each time and recording my elevation(average) adjustment at each distance before moving. From this info I've figured my mv to be on average around 2750fps.

My groups show minimal horizontal displacement but lots of vertical. At 600m it is up to 12" of vertical spread but only 3" of horizontal. I am seeing simiar results in my Lee-Enfield and M1 Garand rifles at 300m using the same loading equipment.

Its either me or my scale I'm thinking? Weird that the other rifles are doing the same with their loads too if it is a powder thing? I know that seems like low mv but shouldn't the bullets travel the same speed and hit the same elevation if the charge weights are consistent? I won't stop until I figure this out. Thinking I'll toss the junk scale first, load up another 100. Try that. If it doesn't improve I'll abandon ship and start over with varget pushing 69grSMKs.

What are you guys' thoughts and advice? I can see where this is very addicting...
 
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What your seeing is deviation in your velocity. Check out the precision reloading articles on 6mmbr and accurate shooter. That will start you in the right direction. A chronograph is very helpful try and get your hands on one.
 
It's velocity inconsistency, as already stated.
Lots of things you could try but I'd get a chronograph first.
Then maybe a primer switch as that's the cheapest thing to change ( assuming you already tried varying your powder charge )
You should work your load up again if you change primers.
Sounds like your charge weights are consistent though so keep that up.
I had good results using varget in 223 but I was shooting 80 grainers.
There's a starting point to try
 
There are so many potential variables. The one weak link I see in everything here is your dies. If these are your standard 2-piece FL RCBS ala $50 dies, is supect that excess neck tension is probably one factor. Match dies are really a good investment for long range shootng - at least the resizing die. The other this is the velocity... 2750 from a 69 grain is really slow but I am not sure what you are basing the velocity on without a chronograph, sorry, I guess I didn't understand where you got the number. I might suggest for the distances you are shooting, try an AR bullet like the 77 grain Berger or Sierra. You might even get a 75 grain amax to work, but I know some that have trouble with 9 twist barrels. for fun, it might also be worth letting someone else try shooting the same set-up and see if their results mimic your own. Shooter technique at 600 (we ALL have occult bad habits we don't know about) may be a bigger factor than you/i think and chasing down a technical problem in the absence of appreciating shooter input may be a wild goose chase. don't sweat it, trouble shooting this sort of stuff is 3/4 of the fun if you ask me. You'll get there.
 
5440fight said:
Get a mirror. ;)
Click to expand...

Ha ha thanks!

I used a ballistics calculator on my phone and changed the MV input until it displayed the real world bullet drops I was seeing, again I know its not proper but I did it and at least its something of an idea.

I'm replacing that scale anyway, I don't trust it. But I had better look at a chronograph and different components too.

Anyone have experience using Ramshot Tac in a 223 for precision? I've been reading lots on here and haven't found anyone else who has tried it. I'm almost out of it too, so thinking I might try something else. Maybe a powder like varget with 75-77gr bullets? I also have tons of H4895 for my milsurps is it worth trying since its handy?

Dies: they are run of the mill 223 dies but I am only using the neck sizer not the FL die.

I have tried re working this load twice now, once before bedding and once after, same charge seemed most consistent.

Thanks for the suggestions everyone. Now I've got more to work with again.
 
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Are you still using the factory Savage plastic stock?

If you are I'm sure its not helping you in any way.

I can't see the powder charge causing the vertical spread. When doing vertical load testing at 600 yards you probably won’t see 12" of spread even when shooting with 3 grains difference in powder.

Unless your weighing your powder by pouring it in the palm of your hand.
 
That barrel will shoot long range best with a 75 gr HP match bullet or the Sierra 80 gr Matchking.

You need lot of velocity. ReLoader 15. Start at 23 and see if you can go more. My rifle has a deep throat to take the 80 gr and groups about 10" at 1000 yards.
 
Ganderite your rifle has a modified throat to run that long bullet? That twist is fast enough for 80gr'ers? I may get some 75s or 77s then and try those. No one else had suggested ReLoader 15, but some of the guys at milsurps said they use it in their 4T's with success too. Might be another good powder to have on the shelf.
 
flying pig said:
Even with the aluminum bed in that stock its no good?

There is definitely a problem going on here then...
Click to expand...

Except you said yourself that you see similar results with your Enfield and Garand.

What is your cheek weld like? Inconsistency there will also produce vertical stringing. Though it is not the most common cause of the problem you are having, some of the other ones kind of rule themselves out. Having said that, if you can get the use of a chrony, do it.
 
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K chrony is next on the list for gear purchases.

I have worked on my weld quite a bit in the last year. It has been a bit of a problem before, maybe the old habit is back.

I'm going through the stickied videos up top to see if I can find anything else that may be me at fault
 
I've been having good luck with the 77SMK's/Varget out of that same barrel. During my load development I chrono'd every 0.2 grains all the way up to maximum. I entered the data into Excel and calculated the Average, Mean, Std.Dev and Extreme Spread for all the loads. I focused on the loads with the best numbers. My best groups at 300 have very little vertical dispersion and came from a load that was only 0.2 grains off where the math predicted.
Buy a Chrono :)
 
Jordan what is your barrel length? Would you mind pm'ing me what you are running for charge weight?

I only had enough time to go through the basic scope set up video and do the set up on my rifle, cheek weld could be a contributing factor as well, I wound up building a 1" pad and then moving my scope ahead 3/4 of an inch. Much better now. I have enough tac left to do a little more playing with it, another 50 rds or so I would guess. After that I will try the RL15 and Varget with some heavier bullets. I'll buy a Chrony and a better scale as soon as I can too.
 
JBM has a calculator for the relative stability of bullets under various conditions, when you’re looking for something heavier. You can plug in diferent bullets and see how they compare. I found it useful.
h ttp://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi
 
I'm shooting a Savage 12FV all stock. I added a cheek riser and a 10-50x60mm Sightron Slll scope. I have the trigger set at 3.5 lbs and use a two die rcbs on a Lyman Turret press loading 24.5 gr of Varget checked with a electronic and balance scale into a Nosler brass with 69 HPBT Sierra match bullet. I'm getting 2800 fps. I then use my Hornady concentricity gauge to straighten out the bullet to 1000 of a inch! I think you must do this to achieve accurante consisted loads! You need to have tight groups at 200 yards to have consistant groups at 500 yards. I found that with my gun using any bullet over 75gr was pointless with the 1-9 twist! Each gun is different I know but thats just my $.02! You can see my outfit on the My gun can shoot .5" groups all day long post! Good luck and good shooting!
 
flying pig said:
That twist is fast enough for 80gr'ers?
Click to expand...

A 1-9" twist is nominally not enough to stabilize Sierra 80s. It's right on the ragged edge, and there's no guarantees that it will work

HOWEVER, oftentimes it does work - so it is worth trying. Because it's marginal, it's important that you load it as hot as possible (consistent with safety and with maintaining topnotch accuracy).

Note that in cold weather it might simply not work. In which case I suggest you try again once the air temps warm up to 10C or so. I had a 1-9" twist .223 which would shoot 80 Sierras into half-MOA groups; that is, until the air temp dropped to about 0 Celsius, at which point it pretty much fell apart. (As air gets colder it gets denser - which makes it more difficult to stabilize a bullet).
 
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