im loading 280 rem w/150 bt sp sierra bullets at a start out load of 52.2 grains OF IMR 4831.HELP

[This message has been edited by SWAMPFOOT (edited 12-25-2001).]

What type of rifle? Factory production or custom barrel? Where did you get the cases? Have you shot factory ammo in it?

Marks on the shoulder are unusual UNLESS you are over-crimping the case. This is a fairly common newby mistake. When it happens the case sort of caves in and bulges out a little at the neck or shoulder.

Take a resized case (without bullet) and neasure it. Is it less than 2.540 overall?(preferably 2.535 ?) Check to make sure that your seating die as currently set up does NOT try to roll-crimp the (still empty) case mouth. This may require backing off a lot more than 1/4 turn!

Next take a sized case and work a bullet back and forth in the case mouth until it moves easily but does not fall out. (They also sell gimmicks to do this measurement.) Then put a new bullet in it, seated long, and chamber it. When you extract the case, (if the bullet is still in it) you will have a (very) max COL for that bullet. Start out seating the bullets .010 shorter than measured, or to magazine length, whichever is shorter. You adjust the seating depth with the stem, not by moving the die.

HTH,

Don

This technique will ensure that the seating die is set so that cases will go into it to the maximum depth without being crimped. If you screw the seating die down more, it will crimp the mouth of the cases when you raise the die to maximum height.

If you do want to crimp the bullets in your cases, I recommend that you do it in a second step -- don't crimp the bullets while seating them, but instead seat them first, then back off the seating stem and screw down the seating die so that it will crimp the bullets in place. This means that first you would load all the cases in the batch (because you don't want to change the die settings while loading), and then change the die so that it crimps the bullets.

To get the bullets seated to whatever overall cartridge length you want, first set up the seating die as I've described. Then charge the case with powder and seat a bullet on it, with the seating plug set so that the overall cartridge length will be greater than you want. Then take the now loaded cartridge out of the die and measure it. Then turn down the seating plug a turn and run the cartridge into the die again. Measure it again. Repeat this procedure, turning down the seating plug a bit each time, until you have the bullet seated to the overall cartridge length you want. Then tighten down the lock nut on the seating plug. Once you've done this, the cartridge overall length will be fixed so that the subsequent cartridges you load will all be to the same length. Measure the second one to be sure. If it's slightly too long, as it frequently will be, then adjust the seating plug down another tiny amount -- maybe 1/10 of a turn, and measure the OAL again. Repeat this procedure again until you get it to the length you want. After that, the rest of your loads will all be the same length, within a margin of error, assuming that you've tightened things down so that they don't slip or move.

The technique I've described will be the same regardless of the brand of loading dies you are using.

[This message has been edited by LE270 (edited 12-25-2001).]

Your comment that the brass had been "loaded 5 or six times" by your buddy. Get new brass so you know what's been done to it and that it's all the same.

I have tried many methods to find max COL, including Stoney Point gadget. My two favorites are:

Take fired case and gently squeeze with a pair of pliers so that it is slightly out of round. Then, seat a FLAT BASE bullet upside down in the case and chamber it. The flat base of the bullet will be "stopped" by the rifling and pushed into the case (make sure you use a relatively long bullet for the caliber..lighter/shorter bullets may be too short for this to work). GENTLY remove the case/bullet. You now know the length where the OGIVE of a bullet will TOUCH the rifling. Using one of the gadgets described at the to of this post, you can now get close enought to set your dummy round and use the magic marker technique.

Easier, but slightly less precise:

Close bolt on empty rifle chamber. Insert wooden dowel from muzzle end of barrel until it rests against the bolt face. using a razor blade, or very fine mechanical pencil, mark the dowel exactly at the muzzle end. Remove the dowel. now, holding the rifle muzzle down with bolt removed, drop a bullet of the type you'll be loading point first into the chamber. Return the rifle to horizontal. Using a cleaning rod or another section of dowel, insert said dowel from the rear of the receiver into the chamber so that it is gently touching the base of the bullet and holding it against the lands of the barrel. Repeat the measuring procedure with the dowel. (This is sometimes hard for one person to do, you sorta need a third hand...) The measurement between the two marks on the dowel is APPROXIMATELY your COL for the bullet being AGAINST the lands. Again, make a dummy round and test this assumption with the magic marker method.

A few notes:

Always measure at least two times using any method. When I use Don's method described earlier, I use a permanent magic marker and blacken the lower part of the bullet. This is so if the bullet "extracts" from the case slightly upon removal you will see where the marker ink is scraped off. then you can push the bullet back in to that point and measure. I believe this is the method described in Nosler Reloading Manual 4.

Most of these methods are approximations and you will want to always make a dummy round to check. As you know, loading a round with the bullet seated into the lands is DANGEROUS.

If you have a neck sizing die, the "upsidown flat base bullet method" is easier if you neck size a case so that it provides resistance, but so you can still close the bolt with firm pressure. If the bullet is wobbly in case I always worry about the accuracy of the meausrement or that the bullet has moved upon opening the bolt...

Good Luck!

Roger

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Originally posted by SWAMPFOOT:
one thing that bothers me is that when i measured the col it fluctuates on my calipers from one round to the next say 3.285- 3.283- 3.280- 3.283.5 and that may be me not used to using calipers

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The differences you are getting are thousandths of an inch. I wouldn't worry about that, as I think it's too small to matter. I think that as long as you are accurate to two decimal places (hundredths of an inch), that is sufficient, certainly for now as you are beginning to load, anyway.

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Originally posted by SWAMPFOOT:
am i supposed to be really tightening the lock nuts down say w/wrench because i havent i have for now just have them hand tightened that is the seater stem and the locknuts on the sizing dies. i really dont think they are moving though because i have visually marked them in relation to a point onthe die.

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Different dies have different locknuts -- some RCBS dies, for example, have locknuts that are designed to be tightened with a wrench, and the locknuts on other RCBS dies are round so you can tighten them only with your fingers or with pliers. In those cases where I use dies that have locknuts that are designed to be tightened with a wrench, I usually use a wrench. But I don't think it's really necessary, so long as things are tight enough that they don't move while you are using them.

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Originally posted by SWAMPFOOT:
do i need to seat the bullet a little deeper to say 3.280 since it seeems thats where my gun is putting it.
(edited 12-25-2001).]

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The short answer to your question here is yes. In fact, I'd recommend that you seat it at least a hundredth of an inch deeper, to maybe 3.27.

Different rifles behave differently -- some rifles and/or loads give best accuracy with the bullet seated to touch the lands, and others do best with the bullet backed off a bit. Some rifles -- the Weatherby magnums are a good example -- are deliberately made with freebore, meaning that the barrels are bored with some distance between where the bullet lies and where it touches the lands, so that it has to travel that freebored distance before it reaches the rifling.

For someone just learning to load, I recommend that you don't seat the bullets too long until you gain more experience and confidence in your loading and shooting.

The methods recommended by the others here to determine the "correct" or desired seating depth will all work, and having one of the special tools to measure this is a plus. But you can also proceed by trial and error, as you've done, loading a bullet and then seeing if your rifle will close on it. If it will, then fine. If not, then seat it deeper and deeper until it does close without force.

On the question of crimping the bullets, there is disagreement. Some people think that crimping the bullets improves accuracy. Others don't crimp. I don't think that benchrest shooters, for example, crimp their loads. I recommmend that you not crimp your bullets for now, until you've done a fair amount of loading and shooting and have some knowledge of how your loads are going and how your rifle is performing with them. Then, after you've done that, you can try crimping to see whether it improves your accuracy.

Some people think that hunting loads should be crimped so that they will not change while being carried around, or under the forces of recoil in the rifle's magazine, etc. That may be true. But for now, I don't think you should worry about that.

[This message has been edited by LE270 (edited 12-26-2001).]