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Discussion Starter · #1 ·
Hi-
When bullet makers or powder makers put out loading data, they always throw in the OAL. I noticed that sometimes OAL varies with the same bullet between publishers of data.

Is this used so you can compare the OAL with the pressure level?
Or mainly so you know what length the round should be for proper feeding? Or both?

Along the same lines- I'm beginning to start reloading and will use 230gr LRN from precision (45acp). Should I just stick to the standard OAL that everyone seems to go by- 1.275 or use what the powder maker publishes when showing their recommended charges??


Thanks!
 

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The data for the manuals are for the specific combination of components listed. If you use different components and shoot them out of your pistol it will be different but probably close. The differences between data for the various manufacturors can be for a lot of different reasons from bullet design to the barrel they shot the loads from. I will glance at a couple of my manuals to get a ballpark figure and just work from there. If you are using a specific manufacturors bullet and they have a reloading manual that lists data for that bullet, they would be the best source in my opinion. As long as you are not trying to make maximum top end loads or minimum low end loads there is generally a pretty wide area to play with in regards to OAL and powder charges.
 

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I also use precision bullets, I love them, anyways, I use 3.9 of Titegroup and load to 1.250 OAL, that gives me a power factor of 170 out of a Colt GM series 80.
 

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Discussion Starter · #4 ·
Trek,
WHo makes tightgroup? I'm not very familiar with them.
Is a powder like Bullseye?
 

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The SAAMI spec for .45 ACP RN is 1.275" maximum - no minimum length is specified.

Most manufacturers load to a significantly shorter length, as you can verify with calipers; this ensures that the cartridge will feed in a wider variety of firearms.

My Para-ord feeds 1.240" well, so I load everything to 1.240 max; this also feeds well in my Colt, Springfield, etc.

Try to find an OAL between 1.180 and 1.275 that will work in all of your toys, then work up loads for that OAL, and hope that new acquisitions will not force you to change OAL.

I know a lot of people will wonder why I do this, but my really reliable guns will chamber an empty case, fed from the magazine when the slide release lever is lowered. That tells me that the gun is indifferent to bullet shape and short OAL.
 

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Discussion Starter · #6 ·
Thanks! I'll keep those OAL numbers handy.
I too, did an empty case feed test with my 1991 commander. I was amazed that it feed the resized empty casings without a problem. Pretty amazing.

Is there a minimum OAL that anyone knows of (45acp) that one should never use?

Thanks!
 

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OAL

Hey David:

Sounds like you're having fun reloading. Good. Let me squander a perfectly good opportunity to stay quiet by jumping right in here. OAL isn't my favorite topic but it is in the top 10.

SAAMI specifies max OAL. That tells folks how big chambers, magazines and so on must be as a minimum to accommodate the longest cartridges.

Reload manuals specify an OAL for, as previously stated, a specific recipe. This you must take as the minimum. Shortening OAL below this mark without an appropriate adjustment in powder charge will raise pressure. The increase in pressure can be pretty dramatic, especially in cartridges which have small case volume. There is a discussion on seating depth that could go here but would probably just muddy the waters.

In any case, the OALs referred to above are not to be confused with the OAL you are going to want to settle on for a given load to ensure feeding and produce best accuracy. You will want to be at or above the min OAL from the recipe and at or below SAAMI max. That's probably obvious to you.

Here's what I do for the .45 ACP:

Long ago I put a WW white box 230 gr 45 ACP fmj round which I knew my gun to love, into the seating station and adjusted the round nose stem to just touch the bullet at the end of the stroke.

I locked that adjustment in and I load reliable cartridges in 6 different bullet weights and 4 different shapes. Try it You'll like it.

Cheers,

Norm
 

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Norm Lee said:

Long ago I put a WW white box 230 gr 45 ACP fmj round which I knew my gun to love, into the seating station and adjusted the round nose stem to just touch the bullet at the end of the stroke.

I locked that adjustment in and I load reliable cartridges in 6 different bullet weights and 4 different shapes. Try it You'll like it.

That will work for FMJ and other round-nose bullets, but you will not seat truncated cone or semi-wadcutters far enough. You need to be ABOUT 1.225" OAL on flat points.
 

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OAL

Hi Shane:

I beg to differ. I will admit that I haven't tried all possible combos but here's a sammple:

185, 200, 235, 255 SWC

225 TC

200 rn

230 FMJ

200 jhp

I fully expected this to work for the H&G 68 200 swc since it's designed, for reliable feeding, to be seated to match the FMJ ogive. That is it should be seated so that first contact with the feed ramp comes at the same time in the cycle for the SWC and the ball rounds. Ed Brown showed a nice CAD pic in American Handgunner a couple of years back which illustrated the principle. Up 'til then I'd just been too idle to be bothered adjusting the seating die for all the different loads I needed :) After that, there was scientific rationale, eh?

Happily the other sizes and shapes have worked out, too.

Now, I would guess that there are seating dies out there whose stems have not been carefully crafted to match the profile of the fmj bullet. These prolly won't give as good results.

But this should work well for you if you've got decent quality tools.

Cheers,

Norm
you should try it before you say it won't work
 

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Norm Lee said:
you should try it before you say it won't work
I have.

Maybe I'm not understanding your statements. Are you saying that once you've locked down your seating die to FMJ OAL dimensions (say, 1.255" to 1.260"-ish) that you are good to go on various other bullet profiles and ogives? Or are you saying that all your bullets when seated give you an OAL of 1.260"-ish? If so, then you are definitely seating SWC and TC way too shallow.

You cannot get SWC to seat properly at round-nose OAL. The shoulder is too high above the case mouth.

Also, there's a little thing called bullet set-back that you are inviting to rear its ugly head by not seating bullets to the correct depths. It is case pressure (from the sizing die) and to a lesser degree - the amount of crimp - that prevents set-back. If you do not seat deep enough, you simply do not have enough case gripping the bullet, and you will find that your bullets are going to get pushed back towards the primer when they hit the feed ramp as your pistol cycles.

Each cartridge manufacturer generally has a list of seating depths and OAL specs available by bullet type, and I respectfully suggest you use them.

What make of dies are you using?
 

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OAL

Clearly we're not communicating. I need a chalkboard, damnit!

Try to imagine the profile of 230 FMJ. Now imagine the profile of an H&G 200 gr SWC. Lay the latter over the former and see where the edges of the bullet noses first coincide. The FMJ bullet will have a portion of it above the SWC. The rn stem will contact the bullets at the place where there diameters coincide. When the seating stroke is finished, the OALs will be different. Net result is that the bullets contact the feed ramp at the same place in the cycle. This is a feature of the H&G design and the method I propose is exactly the right way to load to match the designer's intent.

I use Dillon dies for my .45.

Crimp, especially taper crimp isn't going to do anything for set back.

What happens if you do not seat deeply enough to get good tension is that you will have squibs.

Cheers,

Norm
 

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Dsonyay, the SAAMI spec for OAL is single ended, that is, they specify a maximum value only. No minimum value exists, and you have demonstrated that by successfully chambering an empty case from the magazine. You have stacked the deck in favor of success, however, by resizing the case before making the test. I am able to perform the same feat when using a just-fired case.

Some say that a dented case is insignificant, because the resizing die removes dents and crushed case mouths; that's true, but deformation of the case indicates that the case experiences one or more collisions with slide, frame, etc before moving free of the weapon. I am concerned that one of these days the case won't exit, but will end up stuck in the gun, causing a FTF. I tune my 1911s to eject brass that has no visible deformation, with the hope that I have eliminated one possible cause of stoppage.

On the other hand, maybe I'm wasting my time...:rolleyes:
 

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Norm,

OK!!!!!!!!! I understand what you are saying, and I agree!

I thought you were (in a nutshell) saying to load all rounds to 1.260"-ish!

I completely agree that if your seating stem has the correct "cut-out" to fit the roundnose FMJ profile, that when you seat SWC and/or TC and/or JHP that the circumference of the base of the seating stem will seat the bullets at (or about) the correct depth. The longer FMJ bullets' noses will push up into the "dished" portion of the stem, whereas the flat nosed bullets will be seated by the base (flat part) of the stem.

I think we're on the same page now - or at least reading the same book!!! :p :)
 

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Discussion Starter · #14 ·
Great advice! Ilike the idea of throwing a commercial round in the seating die to match it perfectly, especially since I'm going to use 230 LRN and FMJ 99% of the time.

With that said, I'm pretty much squared away now. Thanks!
 
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