Shrink group size...some advice or help.

SealTeam4 said:

Did the rifle shoot well at first and then degrade? Or is this how it has shot since the first round?

Joe S.

Click to expand...

Rifle is new and these are basically first test loads. It shoots the 200 ELDX .5" just fine with 96g Reloder 33.

i think you are too close to the lands this soon in developement .. .003 is a pretty small window of error to leave yourself ..

i think there is big differences if one lightly touches compared to just off .. i try to stay away from that line .. unless i can guarantee it never touches

if measured cbto at all exactly .003 off .. when one is "in" your normal run-out tolerances, is it now touching ??.. headspace measurement errors from previous ejector marks and bumps .. thumb presure on caliper

some of these things may or may not matter much ...

DUSTY NOGGIN said:

i think you are too close to the lands this soon in developement .. .003 is a pretty small window of error to leave yourself ..

i think there is big differences if one lightly touches compared to just off .. i try to stay away from that line .. unless i can garantee t never touches

if measured cbto at all exactly .003 off .. when one is "in" your normal runout tolerances, is it now touching ??.. headspace measurement errors from prevoious ejector marks and bumps .. thumb presure on caliper

some of these things may or may not matter much ...

Click to expand...

I never really thought of it that way as far as close tolerances. Makes perfect sense. The wind is screaming today so unless it dies down, I won't be able to try the loads .013 off lands. I'll load some 20 off as well and maybe that's my issues.
I also just picked up some Berger 210's and Berger 215's.....just in case the ELDM's just won't shoot...as wel as CCI 250's
H1000, Reloader 33 and Retumbo is all I have to work with so hopefully I can find what works.

Gotcha. Sometimes you just gotta shoot what the barrel like. It can be frustrating when you have a particular bullet in mind. Cheers

Joe S.

shooters said:

Rifle is new and these are basically first test loads. It shoots the 200 ELDX .5" just fine with 96g Reloder 33.

Click to expand...

shooters said:

Rifle is new and these are basically first test loads. It shoots the 200 ELDX .5" just fine with 96g Reloder 33.

Click to expand...

Sounds like this is your 6th RUM, I'm sure you have a feel for a RUMs barrel life. IMO don't waste barrel life and running around in circles trying to make it shoot something it doesn't like.

Barrelnut said:

Sounds like this is your 6th RUM, I'm sure you have a feel for a RUMs barrel life. IMO don't waste barrel life and running around in circles trying to make it shoot something it doesn't like.

Click to expand...

It is. I've slowly upgraded to the one I currently have....so barrel life does worry me a little when I have to run 100 rounds to find what works.

My starting point with all loads is 0.030" off. I would suggest you start there.

then look at your data and make 5 groups of 5, min to max, and in even increments.

shoot those and tell me if you get a group under 1"

if not, switch bullets. I would go 10 gr higher.

shooters said:

Rifle is new and these are basically first test loads. It shoots the 200 ELDX .5" just fine with 96g Reloder 33.

Click to expand...

It's a seating depth issue to start with. Back it off the lands and it should start making a pattern then you can play with ur powder charge before revisiting seating depth

Canhunter35 said:

It's a seating depth issue to start with. Back it off the lands and it should start making a pattern then you can play with ur powder charge before revisiting seating depth

Click to expand...

Ok. So I took the 12 loaded and put 6 at .015 and 6 at .025 off. I'll go .010 from there on out until things change. Thanks for help

I had a somewhat similar issue with the 212ELD-X, but not as bad. I moved the seating depth to .020, and viola! I use Retumbo, GM215M, and even though I had the ELD shooting nicely, I went back to 210 Berger and 210 ABLR in that rifle.

Well I give up on the 208ELDM. I'm not gonna sit here and try a million things just to get them to shoot, like others mentioned. Here are four pictures.

The first one is Reloader 33 and 94 grains of powder. Bullet seated .020 off lands.
The second picture is same powder and charge, but .035 off lands
The third picture is the same as the first picture (EXCEPT) It's 92g Retumbo .020 off lands.
The fourth picture is 92g Retumbo and .035 off lands.

So basically I did everything the same except used different powder on 2 groups. On all four loads I get vertical stringing.

i'm guessing it's safe to say I won't be shooting 208ELDM bullets?

And just as reference, where my finger is pointing is where I was aiming. And it's at 100 yards.

Another question! Is it possible that what I'm shooting off of could cause this stringing? I'm shooting on an Atlas Bipod 6" and a solid bag at the rear. Gun is rock solid. Is the bipod causing an issue?

Looks like what i got with 7mm eldx. I did find a load but have yet to see if it will duplicate. Id give up too but im stubborn and bought a bunch.

OMG. Almost looks like a rifle/scope issue. I would check everything over. Put the rifle on bags or front rest, and try the 200 ELDX that the rifle liked. I really don't think any amount of seating depth and powder charge changes will really fix that. Get back to ground zero and venture out again if you want to.

hornady bullet either shoot or they don't and you can see from all the post why and how!! The 300 RUM is my favorite 30 cal period and will shoot stupid good. Go
get yourself some h1000, CCI 250, a .338 bushing for .001 NK tension, 215 Hybrid target or even better 230 Hybrid target ( yes contrary to popular belief they will shoot in a 10 twist very well)
start them at 20 thou off load one round from min to well over your max and look for pressure find that back off a gr and shoot for accuracy!! it will take less rounds than you've fired now by half to find what it likes!!!