08-06-2012, 02:05 AM
Here is a little bit of information on loads that work well for service rifle across the coarse competition. Look no further than the Sierra 77 grain SMK for 200 and 300 yard stages and 80 grain SMK for 600 yard loads. It is important that the powder used for short line loads also works without bad chemistry when followed by powder used in the long line load. The simplest way to achieve this is to shoot the same powder. Varget, and Reloader 15 are the most common and successful powders in this application.
It is counter intuitive but the 80 SMK can handle a heavier powder charge when loaded longer than mag length for single loading than the 77 SMK when loaded to mag length.
The Wylde chamber is the most popular chamber in use in .223 for service rifles. If loading for the Wylde Chamber, it is normal that the shoulder of fired cases are .005-.008 inches longer than SAMMI specifications. Cases will last longer if the shoulder is pushed back no more than .003" but then that case can only be fired in a wylde chamber. If that round is chambered in a CLE or other tight dimensioned chamber it will result in a case stuck in the chamber and may not fully close the bolt resulting in a rifle that can neither be fired not the round extracted. This isn't good and should be avoided. One way to do so is to resize cases fired in a Wylde chamber to SAAMI specifications. This will result in fewer loads per case but the risk is not worth taking to achieve a few more loadings per case.
So, assuming a wylde chamber, 24 grains of R15 is a great starting place and is often the stopping place too. Generally loads can be increased up to around 24.5 grains of R!5 under the 80 SMK if it is loaded for a jump to the lands of around .015"
Varget can be loaded a little heavier with many using 24.5 grains for the 77 SMK at mag length and 25.0 grains behind the 80 SMK seated long. Keep in mind you must work up to these loads in your rifle and they will blow primers in a tight chamber.
Many records have been set with the R15 and Varget loads I listed but they don't meter all that well so I don't use them. Instead I load my short line loads with with 23.2 grains of IMR8208XBR and my long line loads with 24.5 grains of Varget. I throw the 8208 loads and assemble on my Dillon and weigh the Varget loads and assemble on my single stage Press. It really isn't necessary to weigh the loads, throwing them is good enough for 600 yards, weighing is really only critical at 1,000 yards but I go ahead with the extra effort just for the peace of mind. Varget follows 8208 very well as they are the same chemistry, I shot five matches this week at camp Perry and every time I laid down at 600 yards with my Varget loads I shot an X or ten on the first shot, no settling required.
Another great bullet pair is the 75 grain Hornady BTHP Match and 80 grain A-Max. I have shot identical scores with this combination as the Sierra and they are typically 20% or more cheaper. I'm shooting the Sierra's only because I lucked into a 50% off certificate from Sierra up to $2000 so they are cheaper for me to shoot this year. However the top shooters opt for the Sierra's at a very high rate.
There really isn't any reason to look at any other bullets for this game, shoot the Sierras if you can or fall back to the Hornadys if funds require. The scores will be shot by the shooter not the load, so put as much time as possible working on position, sight alignment, and trigger control, that will get you more points than any amount of load development.
Bob
It is counter intuitive but the 80 SMK can handle a heavier powder charge when loaded longer than mag length for single loading than the 77 SMK when loaded to mag length.
The Wylde chamber is the most popular chamber in use in .223 for service rifles. If loading for the Wylde Chamber, it is normal that the shoulder of fired cases are .005-.008 inches longer than SAMMI specifications. Cases will last longer if the shoulder is pushed back no more than .003" but then that case can only be fired in a wylde chamber. If that round is chambered in a CLE or other tight dimensioned chamber it will result in a case stuck in the chamber and may not fully close the bolt resulting in a rifle that can neither be fired not the round extracted. This isn't good and should be avoided. One way to do so is to resize cases fired in a Wylde chamber to SAAMI specifications. This will result in fewer loads per case but the risk is not worth taking to achieve a few more loadings per case.
So, assuming a wylde chamber, 24 grains of R15 is a great starting place and is often the stopping place too. Generally loads can be increased up to around 24.5 grains of R!5 under the 80 SMK if it is loaded for a jump to the lands of around .015"
Varget can be loaded a little heavier with many using 24.5 grains for the 77 SMK at mag length and 25.0 grains behind the 80 SMK seated long. Keep in mind you must work up to these loads in your rifle and they will blow primers in a tight chamber.
Many records have been set with the R15 and Varget loads I listed but they don't meter all that well so I don't use them. Instead I load my short line loads with with 23.2 grains of IMR8208XBR and my long line loads with 24.5 grains of Varget. I throw the 8208 loads and assemble on my Dillon and weigh the Varget loads and assemble on my single stage Press. It really isn't necessary to weigh the loads, throwing them is good enough for 600 yards, weighing is really only critical at 1,000 yards but I go ahead with the extra effort just for the peace of mind. Varget follows 8208 very well as they are the same chemistry, I shot five matches this week at camp Perry and every time I laid down at 600 yards with my Varget loads I shot an X or ten on the first shot, no settling required.
Another great bullet pair is the 75 grain Hornady BTHP Match and 80 grain A-Max. I have shot identical scores with this combination as the Sierra and they are typically 20% or more cheaper. I'm shooting the Sierra's only because I lucked into a 50% off certificate from Sierra up to $2000 so they are cheaper for me to shoot this year. However the top shooters opt for the Sierra's at a very high rate.
There really isn't any reason to look at any other bullets for this game, shoot the Sierras if you can or fall back to the Hornadys if funds require. The scores will be shot by the shooter not the load, so put as much time as possible working on position, sight alignment, and trigger control, that will get you more points than any amount of load development.
Bob