max seating depth

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Blue1

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Are there standard max seating depths for .38 Special, .357 Magnum and .45 ACP?

Given those standards, can one load those calibers with data and disregard bullet type, i.e. lead round nose, lead semi-wadcutter, FMJ, plated and or jacketed as long as one observes the seating depth standard?

I am tired of hunting down load data for specific bullet types, if this is a safe practice (don't see why it wouldn't be for a non-cupped base bullet), I'll just measure seating depth myself.

Please confirm or explain the error of my logic.

Thanks,
Blue1
 
I'd guess plenty will respond here with their opinions. But I think if you're getting tired of looking up data for different bullets - just pick one for each caliber and to make it easy, buy a specific bullet that has specific load data for it in the books.

That would be the safe way.
 
Well yeah, that would be the safe way, but given component availability, I frequently have trouble finding data for the combinations I have been able to find, that is the reason for my query.

Blue1
 
Lot of information to wade through in that SAAMI document.

I propose that with a specific load weight of a specific powder, the case pressure will be the same with any bullet, given the same loaded case volume. Assuming the same crimp.

I suspect there will be small differences between jacketed, plated and lead bullets due to bullet-to-barrel bearing area and material that affect the resistance of each to move through the barrel.

The question is, would these variables imposed upon a constant case volume/powder load be greater than, say, 10%? That would be tolerable, as I test my loads at well under what I would calculate to be max.

I will never need to max out loads in any case, but would like to get up to about 1200 fps with the .357 Mag 125 grain JHPs, and would rather get there in a couple of test loads than get there in four steps.

Opinions?

Blue1
 
The proper OAL for a revolver load is, seated to the crimp groove or cannulure and crimped there.

Whatever that OAL measures is the correct OAL for that specific bullet design.

I don't ever bother to measure revolver loads.
Because you can't change it anyway if you crimp them where they have to be crimped.

rc
 
But what about FMJ slugs without a cannulure or crimp groove?

Blue
 
would like to get up to about 1200 fps with the .357 Mag 125 grain JHPs, and would rather get there in a couple of test loads than get there in four steps.
Click to expand...
List what powders you have on hand, bullet make, type and someone may be loading it already. They can point you in the right direction. I shoot home cast.
 
But what about FMJ slugs without a cannulure or crimp groove?
Click to expand...
With the possible exception of some plated bullets, all revolver bullets will have either a crimp groove, (cast lead), or a cannalure (jacketed).

Smooth Bullets without either are made for auto-pistols & taper-crimping.

rc
 
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RC pretty much cleared things up, seat and crimp in the canelure.

As for data, use data specific to the bullet weight and design, as in lead, use lead data, plated, use plated data, jacketed, jacketed data. As long as you aren't starting your work up unreasonably high, in other words, start no more than mid way between start and mid table, you should be fine. I understand what you are saying though, it can be expensive and time consuming to do elaborate work ups for a wheel gun cartridge. I have been starting between mid and start charge for many years, and have never experienced a problem.

BTW, if the FMJ is intended to be used in a rimmed revolver cartridge, it will have a canelure, other wise you are using the wrong bullet.

GS

Oops, RC responded to the FMJ no canelure question as I was writing.
 
I have Berry's and another brand of plated bullet with no cannulure or crimp line in .38 caliber; Xtreme also offers flat point .38 cal plated in that style as well...what would these be intended for, .38 Super?

I have seen no consequences from using these in my 686. What would be the problem?
 
It sounds like you are trying to over simplify the process. The problem is there are too many variables to justify that simplicity. If you follow RC's advice, you will be OK. Crimp into the cannelure. We all have our favorite loads for each of our guns. This took us years sometimes, now with the shortages, we are scrambling just to keep shooting. This doesn't mean we can take shortcuts. You still have to do the work up for each load in each gun. Sorry for the bad news. The bright spot in all of this is you get to shoot more, working up loads is a great way to do it.
 
But to take the OPs question further, he also mentioned 45 ACP. His question has come up probably here and I know other forms.

A specific seating depth rather than a COL??

. No crimp grooves on semi auto bullets so does that leave only the "plunk test" and what chambers correctly?? No deeper than the min COL??

Does published load data take into account the Min COL? Can any cartridge be safely loaded at the MIN length using the published data or just to the tested length??
 
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Pictured below are two 230 gn .45 ACP JHP bullets. A Speer Gold Dot and a Hornady XTP.

Speer%20Hornady%2045%20ACP.png

Note that while both are 230 gn JHP their profiles differ slightly. The Speer is about .020" longer than the Hornady. Does it really matter? I doubt it but lets look at the loading data from each manufacturer.

Using Unique powder
Speer Gold Dot 5.4 to 6.0 grains with a loaded COL of 1.200"
Hornady XTP 5.2 to 6.6 grains with a loaded COL of 1.210"

Do the math.... Assume each case trimmed to 0.890", long as they are in spec and uniform.

The 45 ACP is really a low pressure cartridge with a maximum SAAMI pressure of 21,000 PSI. I doubt that with the seating depth difference between the two it will matter much, especially considering the load ranges. Neither bullet has a cannelure either.

I would load a sample round using what one has (for want of a specific bullet with data available) slowly seating the bullet deeper and deeper trying the plunk test at increments. When the plunk test passes then load observing good loading practices and working the powder charge up slowly from good published data.

Ron
 
Rule3 said:
The case trim length does not change the COL
Click to expand...
Agree but if I have a case trim of .888 and a case trim of .898 with the same COL won't the longer COL have more bullet seated in it? More in less out for the same COL. I just tossed the COL in, not really important.

Ron
 
I've been thinking about your idea and figured I'd check into it some more.

I shoot a 686 and use 2400 for a majority of my loads for that gun.

you're proposing a specific load weight of a specific powder with the same pressure, if all bullets are seated to the same depth.

So lets choose a 158 grain bullet using Alliant's 2400, using the crimp groove or cannelure. That is going to get you to pretty much the same seating depth, so we're good there.

The attached chart shows load data from different sources, and actually I thought there might be enough overlap, that at least a small range would work for all 158 grain bullets.

But, it didn't turn out that way. That is, staying within the load data limits (for safety) I've referenced and all the bullet options.

I'm not finding a single load weight that that isn't over max charge for some or is under min charge for others. We don't have enough pressure data to use to compare all the bullets. So based on load data charge weights, it doesn't work as a general standard, but could work with some qualifiers.

With lead, there is going to be different brinell hardness numbers and limiting velocities so you don't get leading. Maybe if you only include bullets with high BHN and eliminate those with lower BHN's you can choose a common load.

Downloading 2400 will give unburned powder and I would note that 14 grains of 2400 is a very stout magnum load

the crimp grooves and cannelures are going to be based on where the manufacturer put them - to keep them within the chambers - and that's what they used in their testing.

you may find some other powder that you would get enough overlap to come up with a "general" charge weight for all the same weight bullets - or maybe eliminate some bullet choices.

As I mentioned before, Trail Boss is the only one that I know that has a simplified method.

good luck
 

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