.45 auto Keyholing -- Problem Solved

[AlaskanInTexas]

So I loaded a bunch of .45 auto for the first time (first time for this caliber) and took it to the range. Every shot keyholed the target, even as close as 3 yards. Did some research and discovered that it might actually be the result of the air in front of that big slow bullet deforming the paper target before contact, causing the illusion of keyholing. Went back this morning with some cardboard backing and got perfectly round 45 caliber holes! What a relief. Thought I would post this in case someone else ever encounters the same problem.

[SQLGeek]

What kind of bullets did you load? Run of the mill FMJ?

[AlaskanInTexas]

What kind of bullets did you load? Run of the mill FMJ?

The load was Remington 230 grain brass FMJ round nose (0.452) over 4.5 grains of Titegroup with Wolf large pistol primers. Cases were mixed. OAL was 1.25. Shot fairly well.

[sjfcontrol]

What kind of bullets did you load? Run of the mill FMJ?

The load was Remington 230 grain brass FMJ round nose (0.452) over 4.5 grains of Titegroup with Wolf large pistol primers. Cases were mixed. OAL was 1.25. Shot fairly well.

What data source(s) did you use to work up that load?

[AlaskanInTexas]

What data source(s) did you use to work up that load?

I used Hodgon and Hornady data. The .452 bullet was probably not the best choice to start out with, but I had some on hand. I used the starting loads for .451 jacketed bullets (a typo in my earlier comment - the loads were 4.4 grains) and made sure that it was not close to the max load for a .452 lead bullet. In retrospect, I should have developed a load with a different bullet. Do you see anything wrong with this? It shot fine and felt a tad mild.

[sjfcontrol]

What data source(s) did you use to work up that load?

I used Hodgon and Hornady data. The .452 bullet was probably not the best choice to start out with, but I had some on hand. I used the starting loads for .451 jacketed bullets (a typo in my earlier comment - the loads were 4.4 grains) and made sure that it was not close to the max load for a .452 lead bullet. In retrospect, I should have developed a load with a different bullet. Do you see anything wrong with this? It shot fine and felt a tad mild.

Wasn't so much trying to double-check you, as understand what you did, and where you got your info...

Hogdon only lists two bullet types (online, anyway). A 230 gr lead RN and a 230 gr Hornady FMJ FP. The later shows 4.4-4.8 grns and a COL of 1.200

The nearest bullet in Hornady (8th ed.) is 230gr FMJ-RN and shows 4.3-4.8grns and a COL of 1.230 (the extra length being the round-nose, I presume)

Seems appropriate to me. You left it a little long, but I gather the COL is the minimum value.
I'm new at this so working out what others have done helps me see if I'm thinking straight.

edit: the hornady book show a discontinued FMJ-fp at a COL of 1.200, so it is the difference between the bullet lengths.

[AlaskanInTexas]

Someone will undoubtedly correct me if I am wrong (which is good given what is at stake). The COL listed in these resources, as I understand it, is the minimum COL - you don't want to go below this for the load as the pressures will be greater. I went with 1.25 to (a) be on the safe side with pressures given the .452 jacketed bullet and (b) it feeds well for me.

[sjfcontrol]

Someone will undoubtedly correct me if I am wrong (which is good given what is at stake). The COL listed in these resources, as I understand it, is the minimum COL - you don't want to go below this for the load as the pressures will be greater. I went with 1.25 to (a) be on the safe side with pressures given the .452 jacketed bullet and (b) it feeds well for me.

That's what I was thinking -- until...

I read in the hornady book pg 65, "In our loading data pages we list the maximum Cartridge Overall Length (C.O.L.) according to SAAMI specifications. Differences in manufacturing tolerances mean that your most accurate C.O.L. may differ from those published here."

[sjfcontrol]

Hmm, Hornady lists TWO COLs
On the 1st page of the "45 AUTOMATIC" page they list a "MAXIMUM C.O.L." of 1.275"
On the page with the individual bullets, for the FMJ_RN 230 grain bullet, it shows "C.O.L.: 1.230"

My guess is the statement about SAAMI maximum is the 1.275 value
I'm betting the individual bullet COL is a minimum, but they don't say that that I can find.

[Jumping Frog]

Bullets into a paper target will often tear if it's not secured to a firm back material such as cardboard - these tears can be mistaken for key-holing.

I'll admit that the only reason I shoot LSWC in .45 is I love the nice crisp round holes. Not every gun feeds them well, but I like the result!

[JSThane]

Hmm, Hornady lists TWO COLs
On the 1st page of the "45 AUTOMATIC" page they list a "MAXIMUM C.O.L." of 1.275"
On the page with the individual bullets, for the FMJ_RN 230 grain bullet, it shows "C.O.L.: 1.230"

My guess is the statement about SAAMI maximum is the 1.275 value
I'm betting the individual bullet COL is a minimum, but they don't say that that I can find.

The individual isn't a minimum. It's what the manual writers used to develop that particular load.

Actual minimum COL can vary greatly, depending on the bullet shape, weight, amount of powder, and type of firearm. I've got some old .38 Special LWC laying around where the bullet is flush with the case mouth. With a soft charge, that's no problem; but if I were to step up the charge to a warmer load, it could cause issues. Look at the problems with bullet setback and overpressure in the .40 S&W, for a good example.

However, unless you're seriously hot-rodding your .45 ACP, I'd not be concerned with overpressure, but what COL will best feed in your gun. The .45 is a fairly soft round, pressure-wise.

[sjfcontrol]

Hmm, Hornady lists TWO COLs
On the 1st page of the "45 AUTOMATIC" page they list a "MAXIMUM C.O.L." of 1.275"
On the page with the individual bullets, for the FMJ_RN 230 grain bullet, it shows "C.O.L.: 1.230"

My guess is the statement about SAAMI maximum is the 1.275 value
I'm betting the individual bullet COL is a minimum, but they don't say that that I can find.

The individual isn't a minimum. It's what the manual writers used to develop that particular load.

Actual minimum COL can vary greatly, depending on the bullet shape, weight, amount of powder, and type of firearm. I've got some old .38 Special LWC laying around where the bullet is flush with the case mouth. With a soft charge, that's no problem; but if I were to step up the charge to a warmer load, it could cause issues. Look at the problems with bullet setback and overpressure in the .40 S&W, for a good example.

However, unless you're seriously hot-rodding your .45 ACP, I'd not be concerned with overpressure, but what COL will best feed in your gun. The .45 is a fairly soft round, pressure-wise.

Well, ok, but your LWC bullets would then list the COL equal to the case length. My understanding is that a flush bullet is not uncommon for LWC. BTW, since you mentioned them, do those bullets have a front and back end? Or does it matter?

[threoh8]

"BTW, since you mentioned them, do those bullets have a front and back end? Or does it matter?"

There are double-ended wadcutters, and hollow base wadcutters in .38. The hollow base version supposedly obdurates (deforms to seal against the barrel) better and shifts the center of gravity forward.



Loaded backwards - cavity forward - it looks like the old British "Manstopper" loads for .455 Webley:


Looks mean, not sure how effective they truly were.

I used a lot of the HBWC's (loaded cavity-rearward, flush with the case mouth) in .38 cases for light target loads, and have no complaints. I can't say they were really any more accurate than DEWC's.