Reloading tolerances

Krieger9 · July 2, 2009, 01:49 PM

Greetings all. I'm new and have begun reloading with my load-master. I'm about 30 rounds in so far and have yet to shoot any off even. I'm wondering, being so new, what tolerances people experience / expect when reloading.

When I ran my first batch I was weighing in the completed rounds and coming up with what seemed like large differences in weight. Basically rounds (.223) weighing in from 11.16 to 11.18 grams. Sometimes I would get them further out and some as low as 11.10 grams and as heavy as 11.27 grams. I was basically chucking those < 11.15 or > 11.20. This was quite a few.

My next set of 10 I measured primed case weight, bullet weight and full round weight and calculated the full - components = powder to avg around 1.5 grams of powder which is a pretty good load in my 1.6cc scoup.

This was new brass and some Remington hollow points. The bullets seem to vary the most. Powder seemed to be closer at +-.05 grams on one measurement but the others were +-.03 grams. The .05 was the first and I haven't reproduced that variance. May be a setup adjustment issue.

+-.05 grams is +-3%
+-.03 grams is +-2%

When I take my 1.6cc scoup and lay out .05 grams of powder in it it is not enough for a single layer of powder granules to cover the bottom. These are cylindical granules of Reloader-15.

does anybody else have figures on what tolerances they are experiencing? What % would someone consider a light/heavy load?

Bailey Boat · July 2, 2009, 02:07 PM

With the calculations in grams I can't tell and won't look up the conversions. Convert to grains and someone might be able to help. I see you're in Michigan, why are you using grams vs grains????

rwilson452 · July 2, 2009, 02:09 PM

Every one else I know measures the components in grains not grams asa gram is just too big. do over using a grain scale.

Krieger9 · July 2, 2009, 02:10 PM

I am loading via grains and run the math that way. I'm just talking grams because once loaded the only way I have to measure is by weight. I could run the numbers for Reloader-15 but don't have my materials here. I'll repost the numbers when I find the powder density.

rwilson452 · July 2, 2009, 02:14 PM

I don't understand. A grain is a measure of weight.

Quote:

Grams versus grains
I am loading via grains and run the math that way. I'm just talking grams because once loaded the only way I have to measure is by weight. I could run the numbers for Reloader-15 but don't have my materials here. I'll repost the numbers when I find the powder density.

Krieger9 · July 2, 2009, 02:27 PM

Yes grains to grams it's about
1 gram = 15.4323584 grains
so .05 grams is about 0.77 grains.
what I didn't know that I so poorly stated was the total grains I was attempting to load I believe closer to 24 grain but don't quote me on that anymore. But that does work out to close to the 3% calculation I had with grams.

If I use that conversion a total powder of 23.15 grains with a +-0.77 grains for a +-3% tolerance. In the single worse case scenario.

23.15 grains with a +-23.15 grains with a +-0.463 grains typical for a +-2% tolerance when excluding single rose measurement.

SL1 · July 2, 2009, 02:41 PM

forget about grams and grains and measure your components separately in either measurement system.

You will find that the cases vary considerably in weight, and that SHOULD be the cause of your completed rounds varying so much. Bullets often vary by as much as a grain, too.

What matters with respect to the weigh is the weight of the powder. That should not vary by more than a tenth of a grain for very small powder charges, and by maybe a half of a grain for large charges. (You do the math if you want to know those values in grams.)

When you weigh the completed rounds, the variance in the CASE weights will usually mask even differences that matter in the other components. So, weighing completed rounds is a waste of time.

SL1

James R. Burke · July 2, 2009, 03:29 PM

SL 1 is correct what really matters is the powder weight in this stage of the game. When you get into it more, and if you are shooting competion matches then you might want to weight sort the brass in groups, but for what you are doing it does not matter. Go to grains instead of grams. Make sure you have some real good manuals. Lee makes a good one, and I try to get one for the make of bullet I will be using. Study them good. Good luck, have fun, and keep it safe!

NWPilgrim · July 2, 2009, 06:04 PM

Agree with SL1.

All measuring of cases and bullets for sorting out should be done prior to reloading. Case weight is not so important as case capacity (measured in cc or grams of water held). Bullet weight can be important if you are striving for absolute accuracy and want smallest variations.

The fact you express weights in grams make me wonder how you are measuring them. Are you using a scale designed for reloading? Most powder scales, wither electronic or balance only measure to the 0.1 grain, not hundredths of a grain.

you may want to step back and re-read the manual instructions to make sure you have the sequence of reloading correct, and that you are using the correct reloading tools and understand the starting and max powder charges in grains of weight.

I would be much more concerned with getting proper and accurate powder charges (safety) before worrying about variance in case or bullet weight. Consistency in powder charge and consistency in bullet seating depth are bigger factors than bullet weight variances.

ETA: Agree also with Burke about having a couple of good loading manuals. Usually the manuals from press manufacturers are excellent, get one from whoever made your equipment if possible: Lee, Lyman (#49 is superb), Speer (RCBS), Hornady (not as impressed as with others). And get a manual for the bullet you moist often reload: Speer, Hornady, Nosler, Sierra, Barnes, etc. Hodgdon has an excellent web site for their powder data (Hodgdon, Win, IMR).

Demaiter · July 2, 2009, 07:39 PM

When loading say .223 with Varget pushing a 69 grain hpbt I'd use 25.0 grains of powder. When making/weighing my powder charge I'd be happy with 24.9 or 25.0 or 25.1 grains. So my tolerance is + or - 0.1 grain on a 25.0 grain charge. That would be a 0.004% tolerance above or below what I want.

For triming case my tolerances are preferably within a few thousands of an inch, like 0.002 max or 0.003 depending how picky I am.

For overall length of round from base of brass to tip I like to see again about 0.002 difference at the most.

If your using the Lee Classic Loader - I think you are because you said "scoop." Measure the overall length of the Lee die and measure the length of a loaded round. If you want the bullet say .005 deeper, adjust the Lee die .005 down.

Blue · July 2, 2009, 10:08 PM

This is all giving me mental indigestion. I would need to be real desperate to be using grams. Every single thing I deal with in reloading with regards to weight is in grains, bullets powder and manuals. Don't understand using grams. Must be some reason, though, just goes over my head.

maggys drawers · July 2, 2009, 10:32 PM

Quote:

I'd be happy with 24.9 or 25.0 or 25.1 grains. So my tolerance is + or - 1 grain on a 25.0 grain charge.

You mean .1 grain ? That decimal can make a BIG difference.

Demaiter · July 3, 2009, 07:21 PM

Quote:

You mean .1 grain ? That decimal can make a BIG difference.

Yes - let me fix that typo

July 2, 2009, 01:49 PM	#1
Krieger9 Senior Member Join Date: June 15, 2009 Location: Howell Michigan Posts: 130	Reloading tolerances Greetings all. I'm new and have begun reloading with my load-master. I'm about 30 rounds in so far and have yet to shoot any off even. I'm wondering, being so new, what tolerances people experience / expect when reloading. When I ran my first batch I was weighing in the completed rounds and coming up with what seemed like large differences in weight. Basically rounds (.223) weighing in from 11.16 to 11.18 grams. Sometimes I would get them further out and some as low as 11.10 grams and as heavy as 11.27 grams. I was basically chucking those < 11.15 or > 11.20. This was quite a few. My next set of 10 I measured primed case weight, bullet weight and full round weight and calculated the full - components = powder to avg around 1.5 grams of powder which is a pretty good load in my 1.6cc scoup. This was new brass and some Remington hollow points. The bullets seem to vary the most. Powder seemed to be closer at +-.05 grams on one measurement but the others were +-.03 grams. The .05 was the first and I haven't reproduced that variance. May be a setup adjustment issue. +-.05 grams is +-3% +-.03 grams is +-2% When I take my 1.6cc scoup and lay out .05 grams of powder in it it is not enough for a single layer of powder granules to cover the bottom. These are cylindical granules of Reloader-15. does anybody else have figures on what tolerances they are experiencing? What % would someone consider a light/heavy load?

July 2, 2009, 02:09 PM	#3
rwilson452 Senior Member Join Date: June 10, 2004 Location: Tioga co. PA Posts: 2,647	Every one else I know measures the components in grains not grams asa gram is just too big. do over using a grain scale. __________________ USNRET '61-'81

July 2, 2009, 02:27 PM	#6
Krieger9 Senior Member Join Date: June 15, 2009 Location: Howell Michigan Posts: 130	Grains Yes grains to grams it's about 1 gram = 15.4323584 grains so .05 grams is about 0.77 grains. what I didn't know that I so poorly stated was the total grains I was attempting to load I believe closer to 24 grain but don't quote me on that anymore. But that does work out to close to the 3% calculation I had with grams. If I use that conversion a total powder of 23.15 grains with a +-0.77 grains for a +-3% tolerance. In the single worse case scenario. 23.15 grains with a +-23.15 grains with a +-0.463 grains typical for a +-2% tolerance when excluding single rose measurement.

July 2, 2009, 02:41 PM	#7
SL1 Senior Member Join Date: November 8, 2007 Posts: 2,001	To answer the question forget about grams and grains and measure your components separately in either measurement system. You will find that the cases vary considerably in weight, and that SHOULD be the cause of your completed rounds varying so much. Bullets often vary by as much as a grain, too. What matters with respect to the weigh is the weight of the powder. That should not vary by more than a tenth of a grain for very small powder charges, and by maybe a half of a grain for large charges. (You do the math if you want to know those values in grams.) When you weigh the completed rounds, the variance in the CASE weights will usually mask even differences that matter in the other components. So, weighing completed rounds is a waste of time. SL1

July 2, 2009, 06:04 PM	#9
NWPilgrim Senior Member Join Date: September 29, 2008 Location: Oregon Posts: 2,346	Agree with SL1. All measuring of cases and bullets for sorting out should be done prior to reloading. Case weight is not so important as case capacity (measured in cc or grams of water held). Bullet weight can be important if you are striving for absolute accuracy and want smallest variations. The fact you express weights in grams make me wonder how you are measuring them. Are you using a scale designed for reloading? Most powder scales, wither electronic or balance only measure to the 0.1 grain, not hundredths of a grain. you may want to step back and re-read the manual instructions to make sure you have the sequence of reloading correct, and that you are using the correct reloading tools and understand the starting and max powder charges in grains of weight. I would be much more concerned with getting proper and accurate powder charges (safety) before worrying about variance in case or bullet weight. Consistency in powder charge and consistency in bullet seating depth are bigger factors than bullet weight variances. ETA: Agree also with Burke about having a couple of good loading manuals. Usually the manuals from press manufacturers are excellent, get one from whoever made your equipment if possible: Lee, Lyman (#49 is superb), Speer (RCBS), Hornady (not as impressed as with others). And get a manual for the bullet you moist often reload: Speer, Hornady, Nosler, Sierra, Barnes, etc. Hodgdon has an excellent web site for their powder data (Hodgdon, Win, IMR). __________________ "The ultimate authority ... resides in the people alone. ... The advantage of being armed, which the Americans possess over the people of almost every other nation ... forms a barrier against the enterprises of ambition." - James Madison

July 2, 2009, 02:07 PM	#2
Bailey Boat Junior member Join Date: December 10, 2006 Location: NC Posts: 365	With the calculations in grams I can't tell and won't look up the conversions. Convert to grains and someone might be able to help. I see you're in Michigan, why are you using grams vs grains????

July 2, 2009, 02:10 PM	#4
Krieger9 Senior Member Join Date: June 15, 2009 Location: Howell Michigan Posts: 130	Grams versus grains I am loading via grains and run the math that way. I'm just talking grams because once loaded the only way I have to measure is by weight. I could run the numbers for Reloader-15 but don't have my materials here. I'll repost the numbers when I find the powder density.

July 2, 2009, 03:29 PM	#8
James R. Burke Senior Member Join Date: January 3, 2009 Location: U.P. of Mich/Quinnesec Posts: 1,897	SL 1 is correct what really matters is the powder weight in this stage of the game. When you get into it more, and if you are shooting competion matches then you might want to weight sort the brass in groups, but for what you are doing it does not matter. Go to grains instead of grams. Make sure you have some real good manuals. Lee makes a good one, and I try to get one for the make of bullet I will be using. Study them good. Good luck, have fun, and keep it safe!

July 2, 2009, 07:39 PM	#10
Demaiter Senior Member Join Date: October 27, 2008 Posts: 242	When loading say .223 with Varget pushing a 69 grain hpbt I'd use 25.0 grains of powder. When making/weighing my powder charge I'd be happy with 24.9 or 25.0 or 25.1 grains. So my tolerance is + or - 0.1 grain on a 25.0 grain charge. That would be a 0.004% tolerance above or below what I want. For triming case my tolerances are preferably within a few thousands of an inch, like 0.002 max or 0.003 depending how picky I am. For overall length of round from base of brass to tip I like to see again about 0.002 difference at the most. If your using the Lee Classic Loader - I think you are because you said "scoop." Measure the overall length of the Lee die and measure the length of a loaded round. If you want the bullet say .005 deeper, adjust the Lee die .005 down. Last edited by Demaiter; July 3, 2009 at 07:21 PM.

July 2, 2009, 10:08 PM	#11
Blue Senior Member Join Date: June 6, 2009 Posts: 113	Units This is all giving me mental indigestion. I would need to be real desperate to be using grams. Every single thing I deal with in reloading with regards to weight is in grains, bullets powder and manuals. Don't understand using grams. Must be some reason, though, just goes over my head.

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