44 SPL VV N110 & the RCBS 44-250-KT
It was requested on a couple other 44 SPL threads that I pressure test VV N110 with a “Keith” bullet in the 44 SPL if I could. Ranchman, in particular, was interested because he had been using 17.5 gr N110 in his 44 SPLs under the RCBD 250 Keith bullet and a 265 gr Arsenal cast bullet. Said he has “shot thousands” using 17.5 gr in his Colts w/o any problems but had yet to find any load data for N110 in the 44 SPL.
I did not have any VV N110 because I had never tried it in any cartridge. I have always wondered how it would do in the 30 Carbine, 32 H&R, 357 magnum and the 44 Magnum as VihtaVuori says N110 is “comparable to H110 and 296”. Alas, a check with the LGS’s only got me a “deer in the headlight look”…… However, Ddixie884 came through by very graciously sending me a pound of VV N110. Many Kudo’s to Ddixie884!
The high heat [been running 115 – 125 the last three months here] finally began falling off allowing me to conduct the test. I had 10 shot test strings in Starline 44 SPL cases primed with WLP primers with the RCBS 44-250-KT cast of COWW + 2% tin, sized to .430 and lubed with 2500+. They weighed 254 gr fully dressed. I had the tests loaded with 16.0, 16.5, 17.0 and 17.5 gr VV N110. The bullets were seated to the crimp groove and a medium heavy crimp was applied with the RCBS seater die.
Test firearm was a TC Contender with a factory barrel that had been shortened to 8.4”.
Attachment 269361
A strain gauge is fixed to the barrel over the chamber at the SAAQMI prescribed location for piezo-transducer pressure measurement. The test barrel has been calibrated/ verified using Hornady factory 240 gr XTP ammunition of which the pressure for that lot was known.
I had intended testing last week but the hammer spring broke during the testing of some Herco loads….. So yesterday with a new hammer spring I was off to test again. The temperature during the test ran 85 degrees +/- with a 10 % humidity. Targets were at 50 yards.
Test results;
The 16.0 gr load of N110 ran 1256 fps, SD 28 fps, ES 75 fps, psi 19,900, group 5.9”
The 16.5 gr load of N110 ran 1286 fps, SD 26 fps, ES 72 fps, psi 21,700, group 4.5”
The 17.0 gr load of N110 ran 1305 fps, SD 18 fps, ES 57 fps, psi 21,900, group 3.1”
The 17.5 gr load of N110 ran 1337 fps, SD 13 fps, ES 36 fps, psi 23,400, group 1.75”
As we see from the internal ballistics and the on target results VV N110 obviously requires 23,000 psi +/- before it burns efficiently. Once it got there the results were indeed very impressive. Appears to me the 17.5 gr load Ranchman is using is a particularly good and safe +P load in the 44 SPL.