PDA

View Full Version : Crabo's 180 grain .357/.38 design - The day off report



imashooter2
11-25-2008, 05:27 PM
A short time ago, I posted some GB boolit loads in a thread crabo started in leverguns. This lead to a series of PMs and finally crabo sending me a nice little pile of his own design boolit and some SAECO #353 lubed with the same Speed Green to use in bore conditioning. It took me a while to get them loaded and shake free some time to shoot, but I finally got there. I had some grand plans of what I was going to do before I hit the range, but when I got there the place was packed! On a Monday afternoon no less. The crowd severely limited my ability to run back and forth to hang targets and fiddle with the Chrony. So I abandoned my plans to do a comparison of Speed Green vs. Carnauba Red on the SAECO and concentrated on getting some chronograph work and a couple of good targets shot with crabo's design. Here is the report...

The boolit:
The picture below shows crabo's boolit below a group buy C358-180-RF. Both are large meplat RNFP gas check designs, but crabo puts about .090 of bore ride in front of the crimp groove. The crimp groove itself is deep. Almost like the scraper groove in the 311440. It carries a single deep lube groove and a generous scraping/lube space in front of the gas check. The crabo design lubed and checked averages 180.5 grains in the alloy delivered. The GB (a mold from the first buy) averages 186.5 in WW + 1% tin.
http://www.imashooter2.com/pictures/crabo-des.jpg

The loads:
I put the SAECO boolits in front of the same 10.5 grains of 2400 that my own like. Crabo's design was loaded 25 each with 11.5, 12.0 and 12.5 grains of 2400 and 25 pieces over 14.5 grains of Lil' Gun. OAL was set at 1.615 (as compared to the GB 1.580). The round feeds smooth as silk in my 1894C with the carrier mod (http://castboolits.gunloads.com/showthread.php?t=7750). Past experience indicates that this OAL would not have worked with my rifle before modification.

The shooting:
My rifle is a Ballard rifled Marlin 1894C. Nothing special about it other than a WGRS aperture rear has been added since my old eyes just cannot use a blade rear on a rifle anymore. I started with the SAECO #353 Speed Green boolits. I'm not sure I believe in bore conditioning, but crabo sent them for same and that's how I used them. The crowd had all the benches full, and I needed to wait for one where I could set the Chrony out of the shade anyway, so I sent them downrange at the 75 yard gong offhand. The gong is a 12 inch plate hung under the backstop. My usual load for the SAECO #353 is 10.5 grains of 2400 and Carnauba Red lube. With that I can tag the gong up in the 90% range and it was the same with crabo's Speed Green samples. If POI changed, it wasn't by very much.

Finally a bench opened at the 50 yard line and I hung paper and set the Chrony. I started with 10 rounds each over the chronograph. I would have liked to have used these as an additional target for group, but the crowd forced me to shoot them all on one piece of paper. Then I hung a few targets and finished the loads with one 5 shot and one ten shot group each. I like to use ten shot groups as the real indicator of a boolits performance. All groups were shot from the bench with a rest placed just in front of the receiver and no rear bag. I make no claims to being any sort of shootist. A scope does much better with my tired old eyes and blah, blah, blah. Enough of the excuses. On to...

The results:
11.5 grains Alliant 2400, Federal case, CCI 500 primer.
High - 1,475 fps
Low - 1,426 fps
Average- 1,453 fps
SD- 14 fps
Kinetic Energy- 845 ft/lbs
10 shot group- 4.3 inches.
Comment- Nicely shaped group, but widely dispersed impacts.

12.0 grains Alliant 2400, Federal case, CCI 500 primer.
High - 1,516 fps
Low - 1,474 fps
Average- 1,499 fps
SD- 14 fps
Kinetic Energy- 899 ft/lbs
10 shot group- 4.5 inches.
Comment- Vertical stringing... shooter? No called pulls, but 9 shots into 3.3 inches.

12.5 grains Alliant 2400, Federal case, CCI 500 primer.
High - 1,568 fps
Low - 1,511 fps
Average- 1,544 fps
SD- 20 fps
Kinetic Energy- 953 ft/lbs
10 shot group- 2.6 inches.
Comment- This is the same load that I shoot regularly with the GB boolit. POI very close to the same.
http://www.imashooter2.com/pictures/crabo12-5-2400.jpg

14.5 grains Hodgdon Lil' Gun, Federal case, CCI 500 primer.
High - 1,753 fps
Low - 1,709 fps
Average- 1,732 fps
SD- 13 fps
Kinetic Energy- 1,200 ft/lbs
10 shot group- 3.0 inches.
Comment- Called pull on the shot to the left. Take that one out and it's 2.3 inches. POI shifts dramatically with the hotter load. Wish I had enough boolits to do more work with this powder.
http://www.imashooter2.com/pictures/crabo14-5-lg.jpg

Jack Stanley
11-25-2008, 08:58 PM
Don't ya just hate a crowded range ? I guess it's both good and bad depending how ya look at it .
Those bullets remind me of the Heavy LBT I use with my .357 loads , I forgot what my load of AA#9 is but it works real well . I'm still working on .38 loads and one of my options is go to the heavy bullet and seat it out a bit . I'm sure it will work with a gas check but I'm thinking of leaving it of and lubing in the Star .

How well does 2400 reduce ? I'm thinking maybe try it in the .38 case , Ive seen load data , just never tried it . The Lil' Gun loads you have look nice , maybe one of these days I'll use up this pile of number nine and try that .

Thanks for your work and range time , it helps .

Jack

imashooter2
11-25-2008, 09:30 PM
I've found 2400 to be pretty flexible and I like that I get good performance without magnum primers.

DJWright
11-25-2008, 10:48 PM
I'm shooting a 180 gr LBT FN GC in my Marlin backed by 16 gr, "lil gun. Have not chrono'd the load, but it will hit a beer can at 300 yards if I hold my tongue just right.

imashooter2
11-25-2008, 11:17 PM
I've gone to 14.9 of Lil' Gun with the GB boolit. No problem in my rifle, but it gets lots of pressure sign in slughammer's. Working up is important.

Minute of beer can at 300 yards is some pretty impressive performance from an 1894C. I doubt I can see a beer can that far out.

crabo
11-26-2008, 12:35 PM
Did they shoot as good, better, or worse than what you have shot before?

12.8 of 2400 and 13.5 of 296 have given me my best groups in my rifle so far.

in a lighter load, 6.5 of Unique and HS6 has shoot really well.

Thanks,

imashooter2
11-26-2008, 04:24 PM
I call them the same as the Group Buy C358-180-RF. I think I would have to shoot quite a few groups to call one better or worse at 50 yards and even then they might come up a draw. But remember, the C358-180-RF is the best shooting design I had tried in my rifle prior to this. That list includes Lyman 357156, 357446, 358311, 358477, Lee 358-150-1R and TL358-158-2R as well as several commercial offerings in RN and RNFP configuration.

It might also be observed that I am not the best iron sight shooter on the planet...