Varied COL ???

[BigBore44]

Hi fellas
Anyone here ever notice when loading up ammo that you get different COL while using all the same components?

I've had it happen and just can't seem to get my mind wrapped around how it's possible/happening?

I set up the dies, lock them in place and start running cases through only to find out that they may be different col...??
I'll use 338WM for example.
Book calls for an col of 3.325" with a 160gr TTSX. I Setup the die, measure loaded case until it comes out 3.325", I lock it down, run another to confirm settings are correct and, then commence to start loading the remainder.
After I load say 10 cartridges, I measure again and might have cases of 3.327, 3.325, 3.328 3.329 etc.

Where does this issues start or how does it happen?
How do I correct it, or should I just load and shoot as long as not too long, as in Not over Max col?

Thanks
Ray

I thought Maybe the bullets and/or plastic tip plays a part in this issue, but I've had it happen with non plastic tipped bullets in other calibers to...?
Don't know!!!??!!

[nolongcolt]

Its not possible to load to 100 percent OAL accuracy. If you are only varying a few thousands, that is insignificant and of no bother. There must be either a slight difference in ogive shape in bullets or thickness differences in case rims. I don't worry about it.

[Fowler]

Anything mechanical will have acceptable tolerances to them, what bullet manufacturers allow is really hard to say. I know talking with a really experienced rifle guy he said a +\- .005" is about all you can do with standard hunting bullets, high end target bullets can reduce this tolerance. What differences you can prove on paper might be tougher to prove out.

[BigBore44]

Thanks fellas. I appreciate the info. I thought I was doing something wrong as I figured everyone else was getting perfect length cartridge's with no deviation from spec...

I have also noticed on most of these new Hornady 338WM brass, my primers (Fed 215) are protruding out of case head just a smidge.
I've fired some and they work fine.

Is this something I should remedy with a primer pocket uniformer or just run with what I have???

Greatly appreciated
Ray

[nolongcolt]

Primers should be just below flush, not protruding or sticking out, as this increases risk for a dud or premature ignition, unlikely but possible. Just below flush. When I take a primed case off the press, I instinctively flip it over and feel the primer. If it isn't below flush I put it back and give a bit more push until it is at least flush. Some primers are not a perfect for some cases. You could measure the height of various primers and compare to the Fed and see if one is shorter and perhaps a better fit to your cases. High primers are just not a good idea.

[BigBore44]

Thanks nolongcolt
I'd measure some but only have the Fed 215. I'm kinda out of time to monkey around with this caliber/gun for this time around. Deer season opens next Saturday 11/19 so as long as I have accurate ammo/rifle combo and, it goes BANG when I squeeze the trigger I'll be good to go.
I will tinker around more later on and get things squared away better.
I will be headed up to my buddies huntin camp on Wednesday or Thursday. If the Number 338WM has any issues it may aggravate me but surely won't take me out of the game. I will just grab another from my small hoard of artillery I always bring and, roll with the punches

I will also have along with me:

308 Win Forbes Rifle
Marlin 1895GS 45-70 Guide Gun
A-Bolt 223 zero'd w/50gr Barnes TSX
1894 Cowboy 44 Mag
Scoped SRH 44mag
Bisley FT 44Spl
Glock G20SF 10MM

My dad has a primary and a backup as well

What can I say, I like to be prepared and carry enough GUNS!

Thank God for pickup trucks and, trailers! lol heheheee
Bob

[zeus]

Start measuring to the ogive on rifle rounds. It will help standardize things for you most likely. Tips on normal bully's can vary, get damaged etc. ogive typically is more consistent and works better for setting jump etc to the lands. Under normal circumstances it's probably overkill but with some of the LR rifles that we have availability to now, it's nice to eliminate every little variable we do have control over. I have even started changing how I measure the powder on rifles to every load is individually measured to the mg. How much difference does it make, who knows but at least I know my charges are good and I can knock that off the list if I have fliers while I'm shooting.

I load my rifles to each idividual rifle/chamber. I can set jump etc to that rifle versus what's in the book so to speak. Sometimes your limited in OAL by the mag box in the gun but if not, work the load up in that chamber/throat and I bet you will see some improvement. You can find accuracy nodes in powder charges/velocity ranges then play with seating depth/jump and see things tighten up even more. Sometime you hit it on the head first shot and you're done

[nolongcolt]

Well you will be nothing if not prepared! LOL!

[BigBore44]

Nov 13, 2016 17:00:42 GMT -5 nolongcolt said:

Well you will be nothing if not prepared! LOL!

Hahahaaa, yeah I reckon...
I'm not taking all of'em to hunt but, will be able to shoot them right there at my buddies camp at a little range he's got set up...
The 223 Browning may see some night time predator calling...
The Forbes 308 and the 45-70 guide gun will get some woods time. That little Forbes is pure heaven to carry in the deer woods. It's also scary accurate, especially being its so light and trim @ 5lb 4oz w/scope & sling

BigBore44

[Yetiman]

If you use something like the Hornady Comparator to measure the bullets at the ojive You will probably find that they are quite uniform indeed, as your seating die contacts the bullet at (or very near) the ojive.

 This is a more meaningful measurement than the OAL as it makes the length more uniform where the bullet is going to contact the rifling, and for this reason you will probably still get very consistent results from your ammo.
 As long as the loaded round fits in the magazine and loads properly, OAL is of little concern, though some rifles have magazines that don't tolerate anything much over spec (Ruger Scout in 308 with polymer magazines for instance).




 Persnickety loaders of rifle rounds will also trim the meplat of their bullets to ensure they are more uniform.

If you really want to maximize accuracy, you can experiment with loading just short of where the bullet touches the rifling, right at the point where the bullet touches the rifling, and with a slight jam to see where you get the smallest groups.   Sometimes you can find meaningful gains, sometimes not.  I have had barrels where I found meaningful improvement, and others that did just as well of better at SAMMI spec.

[Deleted]

Not every bullet in a box is made in the same forming dies at the factory, so quite often you can find small variances in bullet length and profile. strangely enough, one major offender are Sierra Match Kings. This happens with handgun bullets too. It's not a major issue, but it does exist.

[bradshaw]

Ray.... it may be that your seating stem pushes the OGIVE, as designed. Length of bullet from base to tip may vary, and while the bullet bases seat to the same depth, tip length varies. This variation occurs at manufacture in the final swage die. Common to some of the winningest match bullets. Length of lead-tip spritzers may be more uniform----until they are tumbled and handled and fed through a magazine. The .338 Win Mag is a forgiving cartridge, both in loading and shooting. Before I worried about a few thousandths COL, I’d spin the cartridges with a dial indicator on the ogive to check runout, since some dies just seem to be more equal than others, and a bullet doesn’t want to start tilted. If a sizing die produces a tilted neck, the bullet will seat tilted.
David Bradshaw