OAL of 185gr. SWC not making sense to me in .45

[adweisbe]

Here is a picture of the bullets I have been using and what one looks like seated in the case. The OAL of the cartridge shown is 1.238.

Now the recommended OALs I have seen are:
1.195 for the Hornady JSWC - I looked at it and it looks similar but not quite the same as what I have.
1.135 for a JSWC - From my lyman manual, looks almost identical
1.275 for TMJ match SWC - From my Speer manual, there is a note saying loads velocities are 800 ft/sec for target shooting and not at max pressure. I am making power factor so this is probably not for me.

The problem is that when I go lower then 1.238 it doesn't look right. Here is an example from the lyman manual 1.135.

The bullet is deeply recessed in the case and the case rim has is not support. That one was 1.140.

Am I measuring incorrectly or am I referencing the incorrect bullet design?

 

[Lugnut]

I only use FMJs typically but the bullet you posted is seated too deep IMO. IIRC the shoulder of the bullet should at least be slightly above the case mouth. Max length is 1.275 for .45ACP so you have some room.

 

[adweisbe]

I only use FMJs typically but the bullet you posted is seated too deep IMO. IIRC the shoulder of the bullet should at least be slightly above the case mouth. Max length is 1.275 for .45ACP so you have some room.

I went with 1.260 for this bullet. A nice portion of the shoulder is above the case, I would say 25-40% of the shoulder that exists before the lube groove. Eyeballing it compared to the 230 LRN I have been using case volume should be the same so pressures will be the same or lower. The max load for this is supposed to be 17,200 CUP with Titegroup, and 20,000 CUP is the max for .45 ACP right? So I have some headroom.

 

[highlander]

I seat my SWC with just a bit of the top band exposed maybe 1/16' seem to feed fine in my 2 1911's. Have to admit I never actually measured OAL though.

 

[Plink]

My recipe is 200 gr lswc over 4.5 gr Bullseye with an oal of 1.260 that will give you about 850 to 875 fps. I forget the pressure but it's a good safe plinkin load I promise you that

 

[noidlight]

I also use a 200gr SWC with 4.5gr Red Dot with an OAL of 1.240. Feeds very well with both my smith 1911 and my Kimber

 

[GTOShootr]

There was another thread on 185 SWC OALs:
http://www.northeastshooters.com/vbulletin/archive/index.php/t-5317.html

I found the same OAL when I messed with 185s.
"I just made up some .45s with a 185grn lead SWC (Roger's Best Brand). I seated them with just a bit of the bullet shoulder above the top of the case and came out with an OAL of 1.26". It sounds long to me but seating any shorter would leave a sharp edge where the case meets the bullet, and I don't like that for feeding. They just barely fit in my Wilson 1911 mags but should work fine."

I know one of my friends was shooting .45 185JHPs to major with 231 for USPSA. I imagine you could attain the necessary velocity with less powder with lead and still be ok pressure wise.

 

[Gammon]

OAL recommendations are just that, recommendations. The 1.275 figure that is often published is a max length and many guns won't chamber these rounds. The OAL changes according to bullet shape; the idea is to get the nose of the round to impact the frame or barrel feed ramp at the ideal point for reliable functioning. Unfortunately this means that OAL will change from gun to gun and also according to bullet shape. This makes for a lot of trial and error testing.

PS Just to make matters worse I will throw in slide velocity. Many ultra reliable target loads will fail to feed when they are loaded to higher velocity. This is because the more powerful round is driving the slide at a higher velocity and the same round that fed reliably at lower slide velocities will now fail. A great example is the 185 gr jacketed swc target bullet. This popular round was extremely reliable, but I know several IPSC competitors that drove themselves crazy trying to get it to feed at IPSC velocities; they just wouldn't work.

 

[adweisbe]

A great example is the 185 gr jacketed swc target bullet. This popular round was extremely reliable, but I know several IPSC competitors that drove themselves crazy trying to get it to feed at IPSC velocities; they just wouldn't work.

That is the exact load that I am developing, 170 or 175 power factor, can't remember. I don't have a chrono (need too) but it feels about right and is the cleanest lead load I have made so far. I am using 5.3 grains of Titegroup. I could probably back down a little but it shoots very clean. I would shoot 230 grain LRN if it weren't for the extra expense.