Are My Numbers Reasonable?

[rcnixon]

I was the the range today with my 1903 Springfield and a batch of reloads. I am pretty much of a novice reloader but I've been at it for a while and I believe I have the hang of the mechanical process (case prep, priming, powder measuring, adjusting seating depth and crimping properly). I did a lot of 100 .30-06. The cases are FC, the primers are CCI #34, 168gr Sierra Match Kings and 46 gr of IMR 4895. The range has an Oehler chronograph and I recorded the following statistics:

Shots: 28
High: 2621
Low: 2524
Spread: 97
S. D.: 25.47

My question is: how do these numbers look, particularly the Spread and the Standard Deviation?

How can I improve the uniformity, if at all. I measure each charge individually on an RCBS 505 beam balance; I'm sure a better scale would yield better results.

Thanks in advance.

Russ

 

[alwslate]

Your 97 fps spread is likely due to the air space in the 30-06 case that
results from target loads using moderate charges of medium burning
rate powder. This has been well documented in rifles like the M1 Garand that position the powder forward when chambering a round. Try
elevating the muzzle of your rifle before each shot to position the
powder back against the primer and lower your rifle carefully and fire
over the chronograph. This is a common problem with rounds like the
38 spl that have small powder charges and lots of air space and some
powders are worse offenders than others.

 

[papajohn428]

For 28 rounds that Standard Deviation looks pretty darned good! Your case prep has apparently been excellent, you seem to be getting very consistent neck tension. Well done! Boosting the charge in half-grain increments should get you even better uniformity and will lead you to the maximum load for your rifle. How's the accuracy? 4895 is one of my favorite all-time powders.

 

[MichiganScott]

You are a grain or two off max. I've shot at least a couple of thousands of rounds in club level competitions consisting of 47gr. IMR4895 with 174gr. FMJ. Increase as papajohn428 suggests.

FWIW, unless the gun is pointed muzzle down when chambering and firing, I wouldn't worry about powder position.

 

[venomballistics]

I'd agree with stepping that load up a little. the numbers will tighten up in a hurry as you creep up on the sweet spot.
Ive gotten the 06 down into the low teens for SD.

 

[Ron H.]

I was the the range today with my 1903 Springfield and a batch of reloads. I am pretty much of a novice reloader but I've been at it for a while and I believe I have the hang of the mechanical process (case prep, priming, powder measuring, adjusting seating depth and crimping properly). I did a lot of 100 .30-06. The cases are FC, the primers are CCI #34, 168gr Sierra Match Kings and 46 gr of IMR 4895. The range has an Oehler chronograph and I recorded the following statistics:

Shots: 28
High: 2621
Low: 2524
Spread: 97
S. D.: 25.47

My question is: how do these numbers look, particularly the Spread and the Standard Deviation?

How can I improve the uniformity, if at all. I measure each charge individually on an RCBS 505 beam balance; I'm sure a better scale would yield better results.

Thanks in advance.

Russ

Sir, as has been noted, your numbers are very good for a 28-shot string. Improving on them is possible, but will require increasingly nit-picky work.

The easiest thing would be to stop crimping your SMKs. They're not designed for it.

Getting a little more involved, you can switch powders. IMR 4350 produces very fine accuracy in my '03-A3, whereas my Garand loads with IMR 4895 do not. Whether that's a powder/air space thing or what I don't know.

Getting more nit-picky, you can trim your cases to the same length after each firing. This makes for more consistent case neck tension.

You can also de-burr the flash holes in the cases. Not the hole you can see when you look at the headstamp, but rather the inside. Sinclair International sells a tool for this, and you'll be surprised at how big some of those burrs can be. Removing them promotes more uniform ignition and only has to be done once per case.

Hope this helps, and Semper Fi.

Ron H.

 

[2152hq]

Don't crimp the Sierra .30 M/King bullet. They're not made to be (roll) crimped.
That alone should do some to tighten up the numbers, but they're not bad right now.
Should improve accuracy too.
(added..I see Ron H. already mentions that issue in his post.)

Check case OAL, Trim them to length.
You're going for uniformity in every thing.

If your present scale is checking out accurately,,then a new one won't be any more accurate than,,,,accurate.
They can be faster to use and easier to operate in some instances though.

I'm still using a Redding scale I bought in the mid 60's. Works, accurate, no batteries, no buttons, no wires.
I dislike change.

What year is the '03?
Sporter or Military Issue?

 

[Pisgah]

Don't obsess over the numbers -- although they look pretty decent. I have seen loads with absolutely lousy numbers that shot fantastically well, and loads with wonderful numbers that weren't worth a hoot.

 

[Maddmax]

If you really want to drive yourself nuts. You can trickle the powder to the exact grain on the scale. Weigh each bullet on your scale (to be exactly consistant) and do the same with all the empty cases. You'd be surprized how far things can be off weight wise.

That was back in my old old days when we would use any tricks we could come up with to out shoot each other. Now we just load em and shoot em.

 

[rcnixon]

First, thanks for all of the replies. It is a great help to be able to bounce ideas and questions off experienced people.

OK here are some answers to the questions, mostly in the order of the posts:

The loads are being tested in the '03 but are really for my M1s; thus, while I will be stepping up the loads, I will be doing so carefully. They show no signs of overpressure, easy to extract, no flattened primers and no bright rings around the base.

I am not roll-crimping, I am using a light taper crimp, just enough to keep the rounds from falling apart .

I am prepping a large number (several hundred or more) of cases; once I have the trimmer set, I'll leave it alone until I change calibers.

I'll look into getting a flash hole deburring tool and make that step part of the prep cycle.

The trim-to length is pretty spot on, the book says 2.484 and I am at about 2.483. I just can't imagine that thou is significant. The C. O. A. L. is also within spec and the dimensions compare well with LC 72 rounds.

I don't have test weights but I have weighed batches of bullets and compared the deviation and the scale seems to be pretty close. I have a great deal of scientific and engineering training and work in my background so keeping a log and running the numbers is second nature.

The '03 is a 1918 Springfield Armory with a "frankenbolt" It is box-stock military issue. It even has the original barrel. The M1s are a late 1945 Springfield and a 5.5 million S/N H&R. Both are in excellent condition and have original barrels and bolts. The SA is bedded and has a trigger job and an NM front handguard mounting. The H&R is pure issue.

Russ

 

[Ron H.]

First, thanks for all of the replies. It is a great help to be able to bounce ideas and questions off experienced people.

OK here are some answers to the questions, mostly in the order of the posts:

The loads are being tested in the '03 but are really for my M1s; thus, while I will be stepping up the loads, I will be doing so carefully. They show no signs of overpressure, easy to extract, no flattened primers and no bright rings around the base.

I am not roll-crimping, I am using a light taper crimp, just enough to keep the rounds from falling apart .

I am prepping a large number (several hundred or more) of cases; once I have the trimmer set, I'll leave it alone until I change calibers.

I'll look into getting a flash hole deburring tool and make that step part of the prep cycle.

The trim-to length is pretty spot on, the book says 2.484 and I am at about 2.483. I just can't imagine that thou is significant. The C. O. A. L. is also within spec and the dimensions compare well with LC 72 rounds.

I don't have test weights but I have weighed batches of bullets and compared the deviation and the scale seems to be pretty close. I have a great deal of scientific and engineering training and work in my background so keeping a log and running the numbers is second nature.

The '03 is a 1918 Springfield Armory with a "frankenbolt" It is box-stock military issue. It even has the original barrel. The M1s are a late 1945 Springfield and a 5.5 million S/N H&R. Both are in excellent condition and have original barrels and bolts. The SA is bedded and has a trigger job and an NM front handguard mounting. The H&R is pure issue.

Russ

Sir, if the loads are for the M1, don't switch to IMR 4350 or bump up your load too much. You're right in the "butter zone" velocity-wise for 168s in a Garand right now, and changing powders or powder charges will take you out of it pretty quickly. And a slow-burning powder like 4350 is bad for your op rod.

If your loads show signs of "falling apart" without crimping, your sizing die is set incorrectly. Check your die settings. You neither need nor want to crimp SMKs if accuracy is important.

Regarding trim length, the specific number is less important than consistency, so long as you're within the spec. Sounds to me like you're fine there.

You can weigh your SMKs if you want to, but I imagine you'll get tired of it after 100, 200, or 300 of them all weigh within 1/10th of a grain of each other. Been there, done that. Don't bother.

You can also weigh brass and primers, but after you've trimmed all your cases to the same length and deburred the flash holes, you'll probably find that case-to-case variation drops to negligible levels.

I'm curious: If the loads are for an M1, why are you testing them in an '03? If you want to know how they behave in an M1, chronograph them in an M1--ideally the M1 you'll be shooting them in. Individual rifles do differ a bit.

Hope this helps, and Semper Fi.

Ron H.

 

[ArchAngelCD]

You look like you did a very good job.

I agree you should be testing the ammo you built in the rifles you will be shooting them in. Why not shoot them in your Garands?

 

[rcnixon]

Sir, if the loads are for the M1, don't switch to IMR 4350 or bump up your load too much. You're right in the "butter zone" velocity-wise for 168s in a Garand right now, and changing powders or powder charges will take you out of it pretty quickly. And a slow-burning powder like 4350 is bad for your op rod.

If your loads show signs of "falling apart" without crimping, your sizing die is set incorrectly. Check your die settings. You neither need nor want to crimp SMKs if accuracy is important.

Regarding trim length, the specific number is less important than consistency, so long as you're within the spec. Sounds to me like you're fine there.

You can weigh your SMKs if you want to, but I imagine you'll get tired of it after 100, 200, or 300 of them all weigh within 1/10th of a grain of each other. Been there, done that. Don't bother.

You can also weigh brass and primers, but after you've trimmed all your cases to the same length and deburred the flash holes, you'll probably find that case-to-case variation drops to negligible levels.

I'm curious: If the loads are for an M1, why are you testing them in an '03? If you want to know how they behave in an M1, chronograph them in an M1--ideally the M1 you'll be shooting them in. Individual rifles do differ a bit.

Hope this helps, and Semper Fi.

Ron H.

Ron, thanks for the reply and advice. I was joking about the rounds falling apart. There is the lightest touch of taper crimp from the seating die. It is almost imperceptable at the bottom of the lever stroke. Weighing the SMKs was only a rough check on the scale itself, it wasn't to check the SMKs. I know that they are pretty consistant so I weighed a few 168s and a few 150s to see if the scale itself was in the ballpark. I'm not going to bother weighing cases or anything else besides powder charges. I definitely won't be changing powder or moving the charge weight up much or at all based on the advice you and others have given.

I am testing them in the '03 for safety and consistency. I don't want to damage an M1 if I've made a gross miscalulation. Since everything seems to be good so far, my next step will be to chrono the loads in an M1 and shoot for accuracy off a rest.

Thanks all again, Russ

 

[rcnixon]

I had one of my M1s to the range this evening. I didn't chrono the loads because I don't think they'll be much different than shooting them in the '03. They functioned perfectly; I was a bit concerned about cycling but forty-eight rounds went bang with no drama. I was using the bench rest bags as I also wanted to sight the rifle in roughly. Now I know that it isn't the rifle or the ammo, it's me.

By the way, the load is: LC72 case, CCI #34 primer, 46 grains of IMR 4895 and a Sierra Match King 168 gr bullet.

We are lucky to have a 100 M indoor rifle range here in Wake County, NC. That thing is LOUD indoors!

Thanks to all for the help.

Russ

 

[ArchAngelCD]

By the way, the load is: LC72 case, CCI #34 primer, 46 grains of IMR 4895 and a Sierra Match King 168 gr bullet.

We are lucky to have a 100 M indoor rifle range here in Wake County, NC. That thing is LOUD indoors!

Thanks to all for the help.

Russ

If it were my ammo I would load 47.0gr IMR4895. I do use 46.0gr H4895 and 1 more grain of IMR4895. You might see better accuracy with that 47.0gr load...

Don't get me wrong, nothing wrong with the 46.0gr load of IMR4895 I just find 47.0grs to be a better shooter...

 

[dswancutt]

How did your load shoot accuracy wise? That is the ultimate objective. Velocity wise, you are in the sweet spot starting load wise for a Garand. You may have to go up or down to get the best group.
H4895 & Varget are also good powders.
The CMP forum is a good place for all things Garand and 1903

 

[rcnixon]

From a soft rest, it put 17/20 in the black of an SR-1 at 100 yards. The three fliers were my fault. It scored 190/200. The rifle is an SA, SN in the 3,860,000 range. Bruce Dow of Brooksville, FL bedded it and did a trigger job years ago. It has GI sights and I have old eyes.

Since I want to begin to shoot matches again, I'm working on my upper body and areobic capacity. It's not easy at 62 after coronary artery disease and prostate cancer but I'm walking further, faster and swinging a pair of ten-pound weights. It's good for me anyway.

Russ