How to measure COAL???
- Thread starter chriso
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Best answer I can give you: Published manuals from Lyman, Hornady, Lee, Sierra, Speer, Nosler, ABC's of reloading.
Buy any two and you will have all the answers you'll need in your new hobby.
Lands refer to the rifling in your barrel. They start just after the chamber. If you can load the cartridge so the bullet is very close to the lands (see where the COAL comes into play?) the bullet begins to move but hesitates for a nano second when it contacts the rifling, allowing pressure to build in the cartridge before it finally pushes the bullet down the barrel. The building of pressure aids in uniform combustion and uniform acceleration. This yields more consistent accuracy from rifles built for it (although a marginal rifle will never gain any accuracy at all). Many, many hunting rifles gain very little from it. Many, many surplus military rifles gain little from it. But some gain a lot. You have to be willing to experiment to see how your own rifle responds.
And you have to be willing to read the books. That's where you get your real education. If you ask the same question to 10 guys on Internet forums, you will get 12 different answers and still not know which one is right for you.
Buy any two and you will have all the answers you'll need in your new hobby.
Lands refer to the rifling in your barrel. They start just after the chamber. If you can load the cartridge so the bullet is very close to the lands (see where the COAL comes into play?) the bullet begins to move but hesitates for a nano second when it contacts the rifling, allowing pressure to build in the cartridge before it finally pushes the bullet down the barrel. The building of pressure aids in uniform combustion and uniform acceleration. This yields more consistent accuracy from rifles built for it (although a marginal rifle will never gain any accuracy at all). Many, many hunting rifles gain very little from it. Many, many surplus military rifles gain little from it. But some gain a lot. You have to be willing to experiment to see how your own rifle responds.
And you have to be willing to read the books. That's where you get your real education. If you ask the same question to 10 guys on Internet forums, you will get 12 different answers and still not know which one is right for you.
Hey Chris,
You picked a more difficult cartridge to reload for being a beginner. You should, read a few manuals, talk with one of your friends who reloads, do some rounds with him, and pay close attention. When I started reloading I did it with a good friend, who has decades of experience, started with straight walled pistol rounds, did everything single stage; and did a few thousand rounds that way... WELL BEFORE I ever did anything on my own. Rifle rounds came after all of that.
I'm sure I don't need to tell you but you are endangering your rifle, possibly your life, and others around you if you mess up. I'd start from scratch if I were you.
That's my two cents anyway...
Regards,
Beau
You picked a more difficult cartridge to reload for being a beginner. You should, read a few manuals, talk with one of your friends who reloads, do some rounds with him, and pay close attention. When I started reloading I did it with a good friend, who has decades of experience, started with straight walled pistol rounds, did everything single stage; and did a few thousand rounds that way... WELL BEFORE I ever did anything on my own. Rifle rounds came after all of that.
I'm sure I don't need to tell you but you are endangering your rifle, possibly your life, and others around you if you mess up. I'd start from scratch if I were you.
That's my two cents anyway...
Regards,
Beau
I have talked to a buddy a machinist at my work and he has seen some of my reloads and what not and has been teaching me as much as he can this is just something I have not read about and was wondering how I measure it the first time was I adjusted my die to a factory federal round and now im working from scratch and I dont shoot pistols enough to start doing that I pretty much shoot .308 all the time...
A manual is a must.
.308 is not hard to load, but doing it blind is not a good idea, even with a little help from a machinist.
A good manual is worth its weight in gold when you are getting started. Don't scrimp on that piece of equipment. You will be glad you didn't.
The Lyman is highly touted for beginners.
.308 is not hard to load, but doing it blind is not a good idea, even with a little help from a machinist.
A good manual is worth its weight in gold when you are getting started. Don't scrimp on that piece of equipment. You will be glad you didn't.
The Lyman is highly touted for beginners.
I'm curious, how did anyone know what chriso was loading until he happened to mention a caliber used in many, many cartridges (.308) in post #9? Are we sure it's .308 Winchester?
chriso - please give us some details on the rounds you're trying to construct. Case, bullet, powder, primer, press type, etc. It's not at all clear why you can't achieve the COL you want at this point.
PS - a tip: the Edit button will allow you to change or add to your posts without having to create a new post.
chriso - please give us some details on the rounds you're trying to construct. Case, bullet, powder, primer, press type, etc. It's not at all clear why you can't achieve the COL you want at this point.
PS - a tip: the Edit button will allow you to change or add to your posts without having to create a new post.
It is for a .308 I have a speer manual and a lee manual but did not find that in there thats why I asked... I am using a RCBS rockchucker press with redding dies a RCBS powder measure and 5-0-5 scale... Federal 210 primers,federal brass, and Speer 125 grain hollow point TNT's with IMR 4895... I have loaded the 168 SMK's and 155 SMK's and they were awesome its just the tested COAL for this load in my speer manual is really short and I cant seem to get it down that much im not sure if I even need to is my question really and if I did how do I without pushing the shoulder back and messing up how I resized it???
What rifle? Semi-auto rifle is quite different from bolt action, which is quite different from lever action. And please verify that 308 means .308 Winchester (not Norma Mag, or Marlin Express, or some other 308).
The COAL in the load data is the MINIMUM length. You can always go longer as long as the magazine will hold them. Magazine length is usually the limiting factor.
Go do a search (or reading) on how to determine your chamber length to the lands.
And do a search on this forum regarding 'bumping the shoulder'. We seem to cover it every three or four weeks, might as well do a search and save some time.
The COAL in the load data is the MINIMUM length. You can always go longer as long as the magazine will hold them. Magazine length is usually the limiting factor.
Go do a search (or reading) on how to determine your chamber length to the lands.
And do a search on this forum regarding 'bumping the shoulder'. We seem to cover it every three or four weeks, might as well do a search and save some time.
rcmodel
Member in memoriam
It seems clear that you don't understand how to adjust a seating die.
Lets start over.
1. Put a sized case in the press.
2. Back the seating die out a couple of turns.
3. Run the empty case up into the die all the way.
4. Screw the die back down until you feel the crimp portion of the die contact the case mouth, then back it off 1/4 turn.
5. Lock the die in place with the large lock ring.
6. Back out the seating stem several turns and try to seat a bullet.
7. Keep adjusting the center seating stem down a little at a time until you get the OAL suggested in the manual.
8. Lock the lock nut on the seating stem.
9. Done.
rc
Lets start over.
1. Put a sized case in the press.
2. Back the seating die out a couple of turns.
3. Run the empty case up into the die all the way.
4. Screw the die back down until you feel the crimp portion of the die contact the case mouth, then back it off 1/4 turn.
5. Lock the die in place with the large lock ring.
6. Back out the seating stem several turns and try to seat a bullet.
7. Keep adjusting the center seating stem down a little at a time until you get the OAL suggested in the manual.
8. Lock the lock nut on the seating stem.
9. Done.
rc
Sweet thanks!!! Its a remington 700 .308 winchester sorry for not being specific!!! I tried some speer 125 grain TNT's with 42.5 grains of IMR 4895 with a COAL of 2.768 and I was not impressed by them definite minute of coyote but The best groups I was able to keep were about a 3/4 inch groups...
The Speer #13 discusses COL on pg 77 and I`m sure the other editions of the manual do also somewhere. The Sierra bullets won`t seat to the depth the Speer do due to differences in bullet geometery. You need to adjust to the lenght of your rifles chamber or follow Sierras recommenation for a COL.
Do as other posters have recommended and read the "how to" section of your manual. The Speer is a good book. Lymans manual has more pictures and tips and is IMO a better book for a beginner.
Toss the Lee book. It is no more then a manual for useing their tools with generic data added. Free, newly tested data from the powder makers, is better in most cases, and you should use the instructions from your tooling for set-up and adjustments.
rcmodel
Member in memoriam
SO, what would it take to impress you?
3/4 MOA with a varmint bullet in a .308 ain't all that shabby!
rc
jgh4445
Member
rc, Here's one for ya. I finally got around to getting a comparator. It's a great tool. I also got one of the LNL OAL gauges. Used them together and got a COAL of 3.750 (25_06) which is barely touching the lands. Long story short, with differences up to as much as .020 off the lands, I found the sweet spot. Went back, checked the trim length of the brass, made sure everything was the same and loaded some more. Now when I seat them I get as much as .010 difference! I'm trying for 3.750 exactly and can get as much as 3.740. Here's the strange part. I can start out with 3.750, rotate the round on the caliper with the nose in the comparator as it should be and I get the different readings. Something is moving. Maybe the base of the brass is off? I'm stymied! I hope this made sense.
rcmodel
Member in memoriam
It could be the rifles bolt face is not square with the chamber.
It could be your case necks are crooked.
That can be due to a crooked sizing die.
Or, pulling the expander button out through a dry case neck.
You might try using a nylon bore brush and just a tiny amount of case lube inside the necks before sizing and see if that helps.
I roll a brush on a case lube pad and it picks up just enough to lube necks without getting too much case lube inside the case.
They also sell kits that use powdered mica to do the same thing.
rc
It could be your case necks are crooked.
That can be due to a crooked sizing die.
Or, pulling the expander button out through a dry case neck.
You might try using a nylon bore brush and just a tiny amount of case lube inside the necks before sizing and see if that helps.
I roll a brush on a case lube pad and it picks up just enough to lube necks without getting too much case lube inside the case.
They also sell kits that use powdered mica to do the same thing.
rc
jgh4445
Member
Thanks rc...I'll try the lube. I use an RCBS case prep center and have the lee case trim dies set up like the dude on you tube. Maybe I'm doing something wrong some where. I'll have to take a closer look at what I'm doing.
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