New Loader and COL / Setting Depth

[Vilarin]

I should start off and say I'm really new. I loaded 10 bullets two weeks ago and they fired great I have the Hornady LnL with Lee dies. I'm using Hornady 115 XTP HP, W231, CCI primers, and new starline brass for 9mm. I'm loading 4.5 gr of powder and the COL is supposed to be 1.075. I had the die set for setting the bullet and my first couple were right at 1.075. Continuing on I'm finding the COL fluctuating between 1.084 and 1.065. 1) Does anyone know why the value would be different from bullet to bullet? 2) I was reading in one the manual that COL was considered a maximum, but it could be less. So to avoid having them be to long I ran them through the press again and now they range from 1.075 to 1.062. Am I courting danger with the smaller COL? 3) Does COL really mean a maximum or should you really try and stay close to what the COL is?

Since I thought the originals worked well I made a bigger batch of 50. I do have a bullet puller so can start over if you believe the pressure would be too great by having the bullets seated to low. I was reading some of the other posts, but am a little unsure if I'm understanding them correctly about the COL and seating depth.

Thanks for your help

[Hi-Power Jack]

You're in NO danger. 4.5 grains of WW231 doesn't come close to being a compressed load in

a 9mm case.

As long as the rounds feed thru your mag, and into your chamber, you should be good to go.

You could try to load one round out to 1.11" and see if that will work in your gun/mag, but no

real reason to do that if your 1.065 is working for you.

When you fired the 10 shots, what kind of velocity did you get?

[Vilarin]

Thanks Jack.

I'm not sure about the velocity. I'm new to shooting as well and I'm not sure even how to tell the difference in velocity.

Does anyone have any idea why each bullet would have a different COL as I run them through the press? I have it all set and one may be 1.082 and the next 1.076 and the following 1.071 then the next jumps to 1.081. I follow through when I pull the lever until it stops, so I know I'm not stoping before it is done.

Thanks everyone

[Hi-Power Jack]

Running 1.07 - 1.08 is not uncommon, and not a problem.

More important that the loads are accurate and in velocity range that you're looking for.

You can tell the velocity by using a $70 chronograph - I use the Chrony, and it works

great for me - IMHO, very important reloading tool.

When you fire the next 50 rounds, I'd be interested in what type of accuracy you're

getting at 15 - 25 yards.

BTW, if you're going to be doing a bit of shooting, the XTP's are awfully expensive,

and you'd probably be happier with a heavier bullet (124 or 147 grain).

[kneelingatlas]

You fluctuations in length are normal and are due to slight inconsistencies in the shape of the bullet; you're measuring to the tip if the bullet, but the seating die pushes in the shoulder, so if the shoulder of each bullet is in the same place, the OALs would be different if the taper of the bullets are slightly different.

For an extreme example: I leave my seating die in the same place and get 1.135" cartridges when using plated round nose bullets and 1.100" when using truncated cone cast bullets.

[Vilarin]

Thanks Jack, I'll look into the Chrony. I actually got the XTP ones for free. I figured since I was such a beginner it might not hurt to start my reloading experience by using parts that matched the Hornady manual exactly. I did pick up some regular round nose metal plated bullets which I wanted to use for regular practice, but they were 115 gr. I'll check into higher grain ones next.

Thanks for the insight kneelingatlas. Nice to know that I'm not completely messing up. :-)

[jmbaccolyte]

I should start off and say I'm really new....

You're not really new if you found your way here. I followed the recipes in the reloading manuals for years. It was safe but some manuals (from the sixties and seventies) didn't explain very well why we did what we did. This forum and its members explained why things happened the way they did. You're lucky or smart...