WMR and 105-grain Speer
Made it to the range the first thing yesterday morning and set up the Chrony. My objective for the day was to work towards a successful load using 243 Winchester cases, WMR (Winchester Magnum Rifle) powder, and WW LR primers along with Speer’s 105-grain Hot-Cor bullet.
Researching my manuals I found loading data for Hornady’s 105 grain A-Max bullet. I used the data as a general guide by started low and stopped just .7 grains short of the listed maximum. My goal was to meet or exceed 2800 fps from Remington 788 with a 22-inch barrel. This is a low price rifle, I paid close to $100 new for it in 1979, and it had a 4X scope on it. The rifle is equipped with a Bushnell Banner 3x9 scope. The scope was rebuilt by Bushnell under warranty after I took and fall on snow and ice covered slope. Before yesterdays shoot I had it sighted in for my 80-grain varmint load. I adjusted the scope up a couple of inches but the windage was okay.
Thanks to john keyes and fastchicken I had a feel for factory sporting rifles with a 22-inch barrel velocity.
The weather; during my morning shoot the temperature went from 70˚ to 85˚, RH went 51% to 37%; the wind was steady at 4MPH with Gusty 11 all morning. I could feel the gust push against me. The wind was the biggest negative because it was hitting at approximately 90˚ then shifting to 180˚ and then back to 90˚. Just a little bit squirrelly.
I started at 45.5-grains with a velocity of 2745. The Chrony was setup about 15 feet from the muzzle. You can add about 14 fps for this round to give a muzzle velocity of 2759.
I had five bags of loads which progressively increased to within .7 grains of the published maximum. All rounds function without a problem and there was no primer issues.
I was meeting or exceeding my 2800 fps goal by the second bag.
My final bag gave me an average velocity of 2886 or approximately 2900 fps at muzzle. The picture was from the final bag. I am happy with the results and will not push the load up anymore. I have some new WW bulk brass that I will load a couple boxes out for deer hunting. My comfort level is high with this 105-grain load.
A number of members have stated that they are happy with the 100 or 80-grain factory loads they are using. Their phrase of the factory loads is convincing if I can meet or exceed that velocity and energy level safely I feel I should have a good round.
I have two factory loads at the top of the box, 15 year-old Remington 100-grain CL and three year-old Federal Blue box, 100-grain Power-Shok ammunition. I fired five rounds each across the Chrony.
The CL averaged 2734 at 15 feet, add 14fps gives an approximate muzzle velocity of 2748 fps.
The Power-Shok averaged 2880 at 15 feet, add 14fps which gives an approximate muzzle velocity of 2894.
I have some R-P and FC brass that I have primed. I will load it and verify my top load using the other brass, and get some range practice in. This brass along with the WW test brass came from my varmint brass box. I discarded a few pieces of the brass with cracks or potential cracking before this loading. After inspection but before resizing I annealed the case necks. Some of the brass dated back to when I first started loading for the rifle in 1979.
I have enough new brass that I can load a couple boxes for hunting.
P.S. A little off subject. I have had a Remington M760 for over fifty years, but I have never fired it over the Chrony. My favorite 150-grain bullet for it is the Hornady Spire point bullet. The charge of H4831 I use with it works fine in my 760. But many years ago I noted that the 150-Sierra BT and the Nosler Solid base required a reduced charge. Yesterday I fired three rounds from that 270 across the Chrony with my standard charged reduced by .5-grains behind 150-grain Nosler Solid base.
That old rifle is still on the button at 100-yards, but one round gave me sticky ejection. I will drop the charge .5 grains or more and make another run at it. I will try the remaining rounds in the Remington 700 and see what happens. Traditionally it has handled hotter loads better; A June 1995 entry tells me this was not an accurate load in the Remington 700 with the Nosler Solid Base.
Velocity average 2785 from the M760. In turn my original .5 grain greater load produced 2831 fps at 15-feet from the 22-inch Remington 700 with the 150-grain Hornady and noted to be very accurate.
I love the 270 Winchester but every once and while I think it is more than what I need. (Do not tell my wife.) The .243 Winchester “might” get the job done with a little less destruction. The load I am working with exceeds the “controversial” 1000-pounds of energy beyond 470-yards. The non-hunter will find this offensive, but I enjoy the process of loading a round, sighting the rifle in, and taking game with the round.
Was the 270 Winchester a little too much for a behind the shoulder shoot on this buck? It was my favored 150-grain Hornady load from the Model 700. Would the .243 been cleaner? The 270 hit a rib on entering, creating a 2 1/2 to three inch cone shape whole in the rib cage. Wiped out a lung, and exited the off shoulder with a hole close to two inches. The buck took off and ran a few hundred feet before death.
I believe the buck was programmed to run; he had spotted my movement as I brought the rifle up and he jerked his head around to look at me. His route away from me was in his gps and he put it into gear a nano second after the bullet hit him.