185-gr SWC, Chap. 8: 3000 FPS At Last

[pitted bore]

Part 1

(WARNING NOTE: For the work described below I used my bolt rifle, which has a 1:16" twist barrel with 0.451" grooves. Pressures for reliable semi-auto operation are not a concern. If you try to duplicate what I did, bad things may happen from using different components, different techniques, and different rifles. Be careful. Don't forget that this information is coming to you on the internet.)

This last segment of the 185-grain SWC story introduces no new techniques. It's just a follow-up to Chapter 7 which was about crimping (LINK to Chapter 7). That chapter described how side crimping seemed to solve ignition problems of a straight case full of powder behind a light bullet. With 53.5 grains Lil'Gun behind Hornady's Totally Encapsulated 185-grain SWC bullets (#45137), 8-foot instrumental velocity was 2980 fps. This was really close to the objective of the entire series of trials: 3000 fps.

Below are two concluding exercises. I wanted to find what velocities and problems might result from squeezing a bit more powder behind the 185-grain SWC bullets, and what might be their accuracy.

I used 2X- and 3X-fired cases, and prepped them using Hornady dies with FL resizing and minimal case mouth expansion. I loaded 53-55 grains of Lil'Gun in 0.5-grain increments. Primers were Win SRs.

It was not physically possible to use more than 55.0 grains. For the 54.0, 54.5 and 55.0 loads, powder was trickled in with a 2-foot drop tube, and seating the bullet required heavy compression. To try to gain powder space by seating bullets less deeply wasn't possible; the C.O.A.L. has to be 2.000 inches or less to permit the side-crimp to be applied without distorting the base of these short bullets.

The crimp in these rounds not only served to provide the needed resistance at the start of ignition, but also to keep the compressed powder from pushing the bullet out of place. Appearance of the loaded rounds is shown on another thread: (LINK to image).

After side-crimping, the Hornady taper-crimp die was applied, but it did little. What looks in the image like belling or flare at the case mouth is an illusion. The case mouth was flat against the bullet, and mouth diameter finished at 0.476".

At the range, the center of the chrono screens was eight feet from the muzzle. Air, ammo & rifle temperatures were 48 degrees F. Recorded velocities were:

charge - - - trial 1 - - -trial 2
--------------------------------
53.0 gr - - - 2950 - - - no rd
53.5 gr - - - 2964 - - - 2971
54.0 gr - - - no rd - - - no rd
54.5 gr - - - 3057 - - - 3003
55.0 gr - - - no rd - - - 3050

(A month later now, the resulting shoulder bruises I reported elsewhere (LINK) have finally disappeared.)

There were no obvious signs of excessive pressure from any of these rounds: no sticky bolt lifts, no flattened primers, no radial expansion of case heads, no extrusions of case heads into ejector slot, etc. As noted before, I know that looking at these is the equivalent of reading tea leaves, so I may have been in trouble and not even known it.

The crimping groove was ironed out almost completely. It could be seen as a narrow band on the case exterior, and barely could be felt with the fingers.

So, about a year after starting the project (with lots of interruption), 3000 fps showed up on the chronograph readout, with apparent safety.

[pitted bore]

Part 2

In addition to the series of increased powder, for a very abbreviated accuracy trial I loaded five cases with 54.0 grains of Lil'Gun with the above procedures. I was doubtful about prospects for tight groups from these 185s loaded to high velocity. Results in trials a year ago (LINK to Chapter 1) did not show great accuracy potential.

Some reasons for the lack of accuracy may be these: (1) The side-crimp distorts a significant percentage of the bullet's bearing surface, which surely cannot aid accuracy. The crimped bullets look like an old Herter's Wasp-Waist projectile. (2) The twist rate is pretty fast for the short bullet, which tends to emphasize bullet defects. (3) The extra velocity from the rifle increases the problem. The bullet was designed for firing from a 45 ACP pistol, and it comes out of the rifle spinning about three times faster than from a pistol.

At 50 yards, I discovered these light speedy bullets shoot about 5 inches higher than factory loads. The first shot went over the target board, so I lowered my aim point and the next four went into a group 2-1/2 inches high and 1-1/2 inches wide. As expected, accuracy wasn't very good.

Based on the trials of Part 1 above, at 2922 fps the average velocity was less than expected. I'm not sure why it was lower. Variation was acceptable with SD of 17 fps, extreme spread of 25 fps.

edited to repair url

[pitted bore]

Part 3

Some final comments:

This is likely the final installment of the SWC 185-grain 450B saga. The key to making them go fast is the side crimp, which permits ignition of all the Lil'Gun that can be stuffed into the case. (It's possible that one or two other powders may permit higher safe velocities, but they'll be slower than Blue Dot and faster than Lil'Gun. There are not a lot of powders in that territory on the burn rate charts.)

My false starts in other chapters have been described so other handloaders who may attempt to try the light weights won't have to reinvent the wheels that have flat tires.

Two further projects will build on these experiences. First, I'd like to make some light-weight bullets blow up on their way to the target from being driven too fast. When I described this project a year ago on the calgiuns thread, several posters warned about the possibility of light 45 ACP bullets being destroyed by forces generated at 3000 fps. To avoid this, I selected the Hornady totally encapsulated SWC 185-grain bullets. They displayed no problems, but now I'd like to see whether the blow-ups could in fact happen as predicted.

Second, in seeking high velocities with the 450B, I picked lighter bullets because they usually can be driven to higher velocities. The lightest available .451 bullet, as far as I can discover, is the Barnes 160-grain solid copper XPB/TAC-XP bullet for the 45 GAP. However, at 80 cents each I didn't want to do a lot of trial-and-error work with them, so I played with the cheaper but heavier 185 grainers. Now I think I can start on the expensive lighter bullets with a bit more insight into how to make them go fast.

We shall see.

--Bob

[thebrassnuckles]

i was just looking at some 185 grain hollow points on midway today... this saga has me intrigued.. i may have to try out some of these....

[gunnut]

Some very good work! Thanks! I've been loading 230gr. FMJ, side crimped for my 450B. The sooting at the case mouth and down the side didn't completly go away untill I hit 44grs. of Lil gun. Primers look fine.

[Hoot]

Some very good work! Thanks! I've been loading 230gr. FMJ, side crimped for my 450B. The sooting at the case mouth and down the side didn't completly go away untill I hit 44grs. of Lil gun. Primers look fine.

44 gr! Good Lord! They must've been really hustlin' down the range. I assume they're fairly thick-jacketed? Brand?
Hoot

[gunnut]

I'm using "Zero" they have a good jacket. I do not use copper clad or TMJ too thin. I have had them come apart. Just not sure if they were damaged by the crimp or the speed I pushed them.

[Hoot]

I'm using "Zero" they have a good jacket. I do not use copper clad or TMJ too thin. I have had them come apart. Just not sure if they were damaged by the crimp or the speed I pushed them.

Yeah, the Berry TMJs shed some bits of jacket on me as well, though the majority of the round hit the target sheet at 100 yards. Yeah, I couldn't tell whether it was from the seating job or just what caused it either. The Zeros look like a good product, though I'm a little discouraged at the prospect of the 1000 bullet minimum order. I don't think I've even come close to that amount of shots in my entire shooting life so far. Do you or anyone know if there is such a thing as a 230 FMJ that specs at .452? I realize that .451 is standard for the .45 ACP. Just that if you could find one the was .452, perhaps it would not be as challenging to get good enough neck tension. For all you boolit enthusiasts out there, I know there are cast options to be had. I just prefer jacketed bullets.

Hoot

[gunnut]

Siera makes .4515, They do shoot good. Just a little pricey. The Zeros are .450 and work fine with the side crimp. I picked up 2k and they work fine in my 45acps as well! So, only 1 bullet for 4 guns.

[thebrassnuckles]

http://www.midwayusa.com/viewProduct/?productNumber=916395

Ready..GO!!

how fast could you make these little buggers go?
160 gr barns solid?