.45 acp HP38 loads - low velocity?

[jaybr]

I'm new to reloading, started with .45 acp. My first loads where 230gr FMJ with 5.3 gr of HP-38, they all cycled fine in both my Kimber Ultra CDP and Sig P220 Carry and where accurate so I loaded up about 300 for the range. I've since shot a couple hundred of them, still no issues at all, but I new they where on the low end of the load. This weekend I decided to load a couple hundred more, and I bumped the charge up to 5.5, they still work great and are accurate. I also recieved 1000 185gr Hornady XTP's last week, so I started working up a load for those. I started with the charge around 4.8 and it wouldn't cycle the slide. I bumped it up in steps and got to 5.5 and slide cycles fine and they are accurate, so I loaded 75 of them.

Well yesterday I tried out the new Chrony Beta and I was getting average velocity of only around 700 fps on both of those loads fired from a Sig P220 Carry with 3.9" barrel

230gr FMJ
5.5gr HP-38
1.272 OAL
avg 700fps

185gr Hornady XTP
5.5gr HP-38
1.175 OAL
avg 690.1 fps

For Chrony reference I also tested 115gr Blazer Brass 9mm and got an avg of 1007.3 from a Kahr K9 3.5" barrel, so I think the Chrony was reading pretty accurate.

I'm not overly concerned about the 230gr loads for punching paper, although they do seem a little slower than I expected. The 185gr XTP velocity was a shock, I expected they would be much faster and something just seems wrong with these.

So what am I doing wrong on the XTP's? Does crimp have anything to do with velocity? Should I tighten up the crimp?

 

[freakshow10mm]

Drop your 230gr FMJ down to 1.2 OAL. Hodgdon manual states that OAL does 832fps at a 5.3gr max.

HP-38 is the same exact powder as W231. 5.5gr of W231 with a 230gr FMJ set to 1.2" OAL is a standard and respected load for the .45.

 

[jaybr]

That has been the frustrating part of reloading so far. My Lyman 49th says 1.275, my small Hornady manual that came with the press has data for 230gr LRN and says 1.270, I split the difference.

My new hardbound Hornady book says 1.230

None of my books state 1.2 OAL for a 230 RN, but do for flat nose.

 

[smokey262]

Hornady also says 1.230" for 230gr XTP/HP

 

[rcmodel]

GI issue 230 grain FMJ-RN ball ammo is loaded to 1.266" - 1.271".
That is mil-spec and allows for .005" +/- tolerance.

That is also the length the 1911 is designed to feed.

You can't go by JHP, or FMJ-FP, or other OAL published in reloading manuals because OAL is a factor of bullet shape, bearing surface, and other things.

230 grain ball is supposed to be 1.266" - 1.271" long.

Cast bullets are another matter, because some of them have a slight shoulder before the ogive starts, and some of them have a shorter curve and a rounder nose.

rc

 

[jaybr]

Hornady also says 1.230" for 230gr XTP/HP

I know, I bought that manual Monday after I did the loads on Sunday. I used the Lyman manual which says 1.175 for 185gr JHP.

The odd thing is I would expect that if I have them compressed too short that I would be creating more pressure resulting in higher velocity.

 

[Jim Watson]

Hodgdon uses the 230 grain Hornady truncated cone instead of a hardball pattern roundnose bullet. OALs are completely different. I don't know why, the bullet is not commonly seen. Somebody once posted that because it was seated deeper than RN, it would give higher chamber pressure and introduce a safety margin into the data.

I have not worked with any 185 grain bullets recently but I got 877 fps with 5.9 gr HP38 and the 200 grain XTP. Caution, that is a MAXIMUM load.

 

[gbw]

This looks too low, as if the front screen is being triggered by muzzle blast before the bullet gets there. Try a blast shield or much easier, back up another 15 ft. or so. Also, if you have a 5" bbl. gun there will be endless comparisons. Your results should be in the same ballpark.

BTW, don't overstress about OAL, many many .45 reloads will shorten themselves, sometimes shockingly, as they hit the ramp. I've heard many many people claim it doesn't happen to them and seldom see any where it didn't especially on the upper rds. in the mag. Using new brass, tight dies, taper crimp, and a smooth feeding gun will virtually eliminate it - otherwise it's common, and the stronger the recoil spring the more common. Lead, ball, jhp, nearly all except the sealed military stuff. It never seems to create a problem.

 

[snommittj]

Might not be the real numbers

unfortunately, Chrony brand chronographs aren't known to be very accurate. Especially in different lighting conditions. Check the numbers on bright days and then on days with cloud cover and you might see different numbers from the same load.

 

[The Bushmaster]

Want to pep up those 185 Grain XTPs?

I'm loading 7.6 to 7.8 grains of WSF under 185 grain Hornady XTP with an AOL of 1.190" and getting 850 +/- from a Kimber UCC II (3" barrel).

Accuracy from my Kimber is 5 rounds inside of a 3" dot at 25 yards (benchresting).

 

[243winxb]

Does crimp have anything to do with velocity? Should I tighten up the crimp?

A more heavy crimp gave slower velocity fps when loading lite cast bullet loads in a 45acp.

 

[The Bushmaster]

.45 ACP...No more crimp then it takes to remove the bell...

 

[Steve C]

I've chrono 5.5 gr loads using W231 which is supposed to be the same thing and they chrono'd at 795 fps with 230gr Remington bulk FMJ's and 200 gr LSWC at 812 fps with the same load. The cases where Winchesters and so where the primers.

Other loads I've chrono'd in both Governement 1911's and my Sig P220 have been very close in velocity with the Sig being no less than 97% of the velocity of the longer barrel 1911.

I have found that primers do make quite a bit of difference in velocity with W231 in the .38 spl the hotter Winchester producing as much as 10% higher velocity than the standard CCI's with the same loading measured on the same day from the same pistols.

The 185gr loads are light for that weight jacketed hollow point and you need to get data from the Hornady manual. Hodgdon's effectively neutered much of the HP38 and W231 data to very modest target pressures and velocity.