9mm C.O.L. Question

[Infantry23]

I'm just starting into reloading and I seated some bullets yesterday. I am using berry's 115gr RN. My Hornady manual says the COL is 1.100. Several questions...

1) is this COL the absolute LOWEST to seat or is there several thousandths wiggle room?

2) if there is "wiggle room," how far is it? I have been using the rule of thumb that if I am within 5 thousandths then I am ok.

3) i have one cartridge that is 1.0945 (5.5 thou short). Is this no-go or am I being obsessive?

4) lastly, do you measure every piece of brass at every step or just spot-check for QC on random rounds?

Thanks for any and all help!

 

[lx1x]

I'm just starting into reloading and I seated some bullets yesterday. I am using berry's 115gr RN. My Hornady manual says the COL is 1.100. Several questions...

1) is this COL the absolute LOWEST to seat or is there several thousandths wiggle room?

2) if there is "wiggle room," how far is it? I have been using the rule of thumb that if I am within 5 thousandths then I am ok.

3) i have one cartridge that is 1.0945 (5.5 thou short). Is this no-go or am I being obsessive?

4) lastly, do you measure every piece of brass at every step or just spot-check for QC on random rounds?

Thanks for any and all help!

Spot check. You'll be fine as long you are not on max powder load.

 

[Infantry23]

Awesome. Thanks. It seems that from what i gather 1.100 is the lowest for COL but i wanted to make sure since i have ocd!

I loaded on lowest charge for accurate #2 so if I am a little short in the COL the pressure won't be too great?

 

[lx1x]

Awesome. Thanks. It seems that from what i gather 1.100 is the lowest for COL but i wanted to make sure since i have ocd!

I loaded on lowest charge for accurate #2 so if I am a little short in the COL the pressure won't be too great?

it will be very minimal pressure change.. that is if you talking about thousands.. tenth and hundreth.. it will make a difference especially when you are on the max powder charge.

berry's bullets varies in height.. they are not your very consistent in height unlike brass encased bullets (fmj).

 

[Infantry23]

Ok. So you only spot check and you wouldnt be worried about being 5.5 thou short on one with minimum charge? I worried and measured almost everything because i was not sure i was doing it correctly!

 

[lx1x]

Ok. So you only spot check and you wouldnt be worried about being 5.5 thou short on one with minimum charge? I worried and measured almost everything because i was not sure i was doing it correctly!

for beginner.. i would suggest measuring maybe every other 5. make sure you have the stroke of the press down path and to make sure the dies are properly setup.


you need worry more if you double charge the case by accident. (thats a different story).

 

[Infantry23]

Thanks! You've cleared up a lot! Last question... with spot checking, aren't reloaders afraid of running into brass lengths and cartridge lengths that are problematic? Or do you measure all brass before starting the process so that properly-set dies produce accurate end product?

I think my ram stroke was too fast maybe.

 

[lx1x]

Thanks! You've cleared up a lot! Last question... with spot checking, aren't reloaders afraid of running into brass lengths and cartridge lengths that are problematic? Or do you measure all brass before starting the process so that properly-set dies produce accurate end product?

I think my ram stroke was too fast maybe.

with handgun loads.. i hardly check the brass lenght, maybe spot check. they dont stretch much unlike bottle neck brass (rifle brass).

 

[Infantry23]

Awesome, thanks!

 

[smdub]

you need worry more if you double charge the case by accident.

x2. I dont think a few thou seating depth makes any difference. The bullet has moved that far LONG before all the powder finishes burning anyway (or maybe even starts burning!).

 

[Infantry23]

Didnt think of that. Makes sense. Thanks.

 

[IndispensableDestiny]

1) is this COL the absolute LOWEST to seat or is there several thousandths wiggle room?

2) if there is "wiggle room," how far is it? I have been using the rule of thumb that if I am within 5 thousandths then I am ok.

3) i have one cartridge that is 1.0945 (5.5 thou short). Is this no-go or am I being obsessive?

4) lastly, do you measure every piece of brass at every step or just spot-check for QC on random rounds?

1. The maximum COAL for 9mm is 1.169 inches. The COAL in the manual is what they used for that combination of components and powder to get the stated velocities and pressures.

2. I usually have no problem keeping the COAL within a couple of thousandths on either side. You are ok with 5 thousandths. I'm of the opinion that variances in COAL come from not "squaring" the seating die and flex in the press frame. But I don't "square" if I am crimping with the same die. I apply the minimum pressure required to get the press ram to stop, no more.

3. I can't say you are being obsessive, but I bet you are using a digital caliper. Ignore the fourth digit to the right of the decimal point. A caliper is not good to a ten thousandth. Five ten thousandths for the good ones, but round up or down in a consistent manner. A good micrometer is good to a ten thousandth, but unless you lay out some big bucks, it will only measure to an inch.

4. I check when setting up the die, obviously, and also when starting up again. I'm fairly confident of my process, the spot checks I do bear that out. I've run a 100 or so rounds and not spot checking until I was done.

It's a good thing to make a sample round for each combination of bullet and brass that has no powder or primer. It makes it easy to set your die the next time.

 

[IndispensableDestiny]

Thanks! You've cleared up a lot! Last question... with spot checking, aren't reloaders afraid of running into brass lengths and cartridge lengths that are problematic? Or do you measure all brass before starting the process so that properly-set dies produce accurate end product?

If you think about it, you'll realize the brass length has nothing to do with variation in the COAL.

 

[IndispensableDestiny]

x2. I dont think a few thou seating depth makes any difference. The bullet has moved that far LONG before all the powder finishes burning anyway (or maybe even starts burning!).

Well, no. If you go too far below the published COAL, your pressures will be higher. If you are loading at or near the published maximum load, that can be a problem.

The does begin burning before the bullet moves. More so depending on the crimp, if any. In a handgun, and many rifles, some of it will not burn at all.

 

[marlin.357]

First it's good you are asking questions, but...

I'm just starting into reloading and I seated some bullets yesterday. I am using berry's 115gr RN. My Hornady manual says the COL is 1.100.

Lets back this up a bit....I don't believe your HORNANDY manual gives you a COL for BERRYS bullets, it give you a COL for a HORNADY bullet. Maybe you're too young for this analogy, but would you use a Ford shop manual to get the timing specifications for a Chevy? (Ans: NO!)

Different bullet manufactures use different profiles for bullets of the same weight and calibre. A 115 gr bullet from Hornady may have a different profile than one from Winchester, Remington, Berrys, Rainier, etc. I have 115 gr bullets from Rainier that measure 0.534 and bullets from Winchester that measure 0.595.

Second, Berrys are plated lead, not jacketed bullets, so you shouldn't be using load data for a jacketed bullet. You didn't say what powder/charge you are using, but as a rule-of-thumb you shouldn't go over a mid-power load for jacketed bullets when using plated bullets.

I'd recommend that you get a couple more manuals, the LEE is good for generic data, and look online at the powder manufacturers website (Hodgdon, Alliant, Accurate, etc.) for additional load data.

Recommend you start at the lowest charge for your selected powder, you will probably find it works just fine. Tweak it up only if you need to make power factor for competition.

1) is this COL the absolute LOWEST to seat or is there several thousandths wiggle room?

The manual should specify minimum COL for the specific bullet, but since you are using a different bullet than specified you might be able to go shorter. Generally safer to go longer, just make sure that you aren't jamming the bullet into the lands, certain pistols have short chambers (CZ). Remove the barrel from your pistol, load up a dummy round, and drop it into the barrel. It should drop in and seat flush with the back of the barrel hood and will make a "thunk" as the case mouth hits the end of the chamber. If it sticks out past the barrel hood you will need to shorten the COL, but not less than the minimum COL. Yes ther are time when you must go below the minimum COL because of the bullet profile, but I'm not going into that now.

2) if there is "wiggle room," how far is it? I have been using the rule of thumb that if I am within 5 thousandths then I am ok.

You should be OK with +/- 0.005. Measure a dozen bullets and you will find they vary in length, and the point where the bullet seater contacts will also vary resulting in an COL variation. Match bullets less so, bulk blasting bullets more so.

Keep asking questions, and study those manuals!