What a deal!!!

C

cdoc42

New member
I reloaded 12 cartridges for my "new model" Remington 700 with Sierra 140gr HP using the Berger suggestion offered by Unclenick in another thread. Everything worked like a charm - changing seating depths at 0.01 -0.05 -0.09 and 0.130 was totally uneventful.

Then I thought about my "old" .270 model 700 that doesn't like anything but 150gr Hornady SP. I have 2 Hodgdon powder bottles full of 130gr Remington .270 CorLokt that I bought in about 1982 from Midway when they were selling these for $36/500. So I thought maybe using the new method would produce surprising results.

And it did. My dummy round measured 2.935" ogive to case base, and the first three rounds at 0.01" were uneventful. When I loaded the second set at 0.05" from the rifling, I reset the die and got the first round to 2.885". The next round measured 2.874". The next one was 2.867". What? is going on?

I spilled a bunch of the bullets on the table and measured the bullet base to give. Here's what I discovered:

Only 4 of 25 measured 0.588". The remaining 21 measured anywhere from 0.539" to 0.574" with only 4 sizes having 2 bullets with the same reading.
Only 1 bullet measured 0.555" and 2 measured 0.560.

I tried these bullets in the past in each of my four .270 rifles at the time (2- Remington 700; 1 Sako; 2 Win model 70). I gave up as accuracy was all over the place.

Now, 39 years later, I think I know why. Maybe this "bargain" at the time was really Remington rejects.
 
That, or the bullets just came off mixed tooling. The ammo makers subcontract a lot. They could also have thrown different lots from different sources into the same container to surplus out. Anyway, try sorting by that dimension to see if matching ones can be made to shoot.
 
That, or the bullets just came off mixed tooling. The ammo makers subcontract a lot. They could also have thrown different lots from different sources into the same container to surplus out. Anyway, try sorting by that dimension to see if matching ones can be made to shoot.
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Good idea, have had issues with that on VLD/ELD types (at least Hornady) so I need to check and sort and then see how they do.
 
"Am just curious, what was your standard for "all over the place"??"

I look for the smallest group possible if I shoot 3, 5, or 10 shots. "All over the place" would be groups 2 inches or more in diameter.
 
"Anyway, try sorting by that dimension to see if matching ones can be made to shoot."

Unclenick, I did that this morning. I separated 12 bullets from the lot that measured 0.558" base-to-ogive. All cases were resized and trimmed to 2.530"; primers were Fed 210; powder was H-4350, exactly 54.5 gr per round. This is the result of 3-shots each at these seating depths:

0.015" - 0.4419" two inches high, 1/4" to right
0.05" - 1.723" - one center, one low left, one high right
0.09" - 1.723" - one center-right, one high left, one high right
0.130" - 0.223" - one inch high, one-half inch to the right

I'll repeat #1 and #4 and chrono them. I will also follow your advice and sort them by dimension.

The bullets I used measured 0.558" base-to-ogive. How do I calculate seating depth of those that differ either higher or lower in measurement based on the 0.558" bullets?

Is the problem with these varying base-to-ogive bullets a different weight distribution, so I can't just make them all the same cartridge base to bullet ogive length-?
 
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cdoc42 said:
Maybe this "bargain" at the time was really Remington rejects.
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I wouldn't be surprised if they are rejects. In the past when I've bought bulk Remington bullets they have been very inconstant for weight but I didn't try measuring the length. I've found that most Midway seconds bullets are better than any bulk Remington bullet. It'll be interesting to see how things shake out with new people at the rains.

Tony
 
Pardon my confusion, but I don't think we are understanding terms the same way. As I understand seating depth, it is the amount of the bullet inside the case.

That being the case, the numbers don't seem right, so obviously I'm not understanding something the same way you are.

Can you explain things in a different way?
that might help me understand better.
 
You're right; my use of the term "depth" is confusing, especially unfair to the neophyte handloader.

The "depths" I listed are distances of that area on the bullet generally referred to as the ogive, seated away from the first contact with the rifling. It is not the bullet distance inserted into the case.

I apologize for the confusion.
 
Going back to my #6 post, I tried to answer my own ending question; let me know if this makes sense.

Bullet #1: Base to ogive measures 0.558". It is seated such that the distance of the ogive from the rifling is 0.02", giving a cartridge overall length (COAL), ogive to case base, of 2.935."

Bullet #2: Base to ogive measures 0.538". If it is seated to the same COAL-OCB, 2.935", the distance of the bullet ogive from the rifling will be 0.02" further away from the rifling, or an actual distance of 0.04."

Bullet #3: Base to ogive measures 0.578". If seated to a COAL-OCB of 2.935" the ogive will actually be 0.02" closer than bullet #1 -which would be right at the rifling.

Now, if adjustments are made such that bullet #2 Is seated to a COAL-OCB of 2.955" and bullet #3 is seated to 2.915", all 3 cartridges would have ogives that are 0.02" from the rifling. Is it reasonable to expect differences in accuracy, even though the bullets are all the same distance from the rifling, due to differences in weight distribution of the bullets?
 
Different nose profiles and weights will produce some degree of difference in BC. Most often it is only going to be significant to long-range target shooting, but it's there. You may want to take the calipers and measure the lengths of the bearing surface (full-diameter cylindrical bullet portion), as a longer bearing surface increases the start pressure which can open groups a bit.

If you are using the Hornady bullet comparator, you can get their case comparator insert and measure the head-to-shoulder dimension and afterward measure the head-to-ogive value with the bullet insert to learn the difference. (Note, the Sinclair stainless steel inserts fit the Hornady holder and contact the bullet lower down where it will actually contact a throat or very close to it, if you want a slightly more exact measurement.) Because the inserts for the case comparator are long to allow them to be used over a seated bullet, the number you get from that difference won't make any direct sense, but that doesn't matter. You are just looking to make those numbers as close to the same as you can. The Redding Instant Indicator can be set up to measure shoulder-to-ogive directly, but it is not an inexpensive tool.
 
Thank you for explaining what you are measuring.

.. listed are distances of that area on the bullet generally referred to as the ogive, seated away from the first contact with the rifling.
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I feel sure I know what you're talking about here, and there are some things I think need mentioning about "loading / measuring to the ogive".

using the definitions found in all the major reloading manuals, the bullet ogive is the entire length of the bullet from the point it becomes smaller than bore diameter and curves or slopes down to the tip. While you are measuring to the ogive, what you are doing is actually measuring to a point on the ogive.

That point being where your bullet first contacts the rifling in your gun. Its a useful and repeatable point with one bullet in one gun. Yours. Or mine, if I doing the measuring, but my measurement is going to be different than yours, I have a different gun and different bullets. I'd probably get a different number than you do if I had your bullets and my gun.

Your numbers about seating depth, and COAL that you use to get the desired 0.02" (or whatever) off the lands only applies to your ammo in your gun.

Is it reasonable to expect differences in accuracy, even though the bullets are all the same distance from the rifling, due to differences in weight distribution of the bullets?
Click to expand...

I'd say yes, its always reasonable to expect differences in accuracy when things are not all uniform in totality. One factor being constant (in this case distance off the lands) but other factors being different certainly can create differing results.

However, sometimes, rifles don't know this, and shoot well anyway. And sometimes they get very picky and find tiny differences enough to misbehave. (larger groups)

Only testing in your rifle can say which, if either, your rifle and ammo combination is.
 
44AMP, your advice is a welcomed addition to the discussion and should be recognized by, not only those handloaders who are just getting started, but for those who might load their own successful recipe in the same caliber and bullet for a friend. You must be sure to match the cartridge to the rifle. Only once in 44 years did I find this not to be the case. I loaded Sierra 52gr HP Match bullets in my Browning .22-250 and a friend was so impressed he bought the same model Browning. I worked up the load for his rifle and the end result was both final cartridges were exactly the same measurement at the stated seated distance. Both barrels must have followed each other on the manufacturing line.

Unclenick, I have the Stoney Creek bullet comparator and headspace inserts, so I can follow through to obtain the data you mentioned. I'll make a series with all bullets being the same COAL-BTOG, regardless of their individual base-to-ogive readings. Then I'll make a series of cartridges with separated, similar B-to-O measurements, adjusted to be the same COAL-BTOG as the 0.558" bullet that gave the good group. But I'll load more than 3 in each series.
 
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