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BigBlack
10-29-2008, 03:23 PM
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Okay I want accuracy plus speed. I know faster does not always equate to better accuracy but I want a blend of both. Here is my game plan on developing some future hand loads. My goal is to achieve the best accuracy/speed combo without wasting a lot of components and since I have started reloading various calibers I am working up a collection of partial powder containers.

Step 1: Load up one cartridge of each weight stepping up in .5 grain increments from min to max. Shoot each cartridge over the chronograph going from lightest charged to heaviest. Watching for pressure signs and monitoring speed. This step is basically to test the upper end of the charge scale and see if it is safe in my rifle and also to see the approximate fps gain for each half grain increment and see if the speed increase flattens at a given point.

Step 2: Once complete with step one load up 3 cartridges each of the top 5 loads from above. Now shoot these for groups at 100 still using my chronograph. If one load shows promise then work around it in smaller increments and more shots per group (maybe 5). If not try a different powder that I have on hand known to work in the cartridge I am loading and repeat from step 1.

Again my goal is to find a good accurate load with upper end velocity. I know sometimes slower is more accurate in certain combinations, but I feel with the right combination I should be able to get both or at least a good balance.

Thinking out loud but thought this would be good food for the brain!

jackie schmidt
10-29-2008, 03:39 PM
Did you ever think about installing a tuner on the barrel.

Seems it would be the perfect solution to your delima........jackie

gzig5
10-29-2008, 04:14 PM
Google "incremental load development" or "Audette test". It is basically your step one, but you shoot on paper at 200-500 yds away. You need to be able to record where each shot falls. You look for clumps of bullet holes from consecutive shots. This indicates a velocity node. Pick several loads from the nodes and shoot for groups. Usually you'll see at least three nodes from a starting load to max.

Greg

Lew
10-29-2008, 05:26 PM
BB, How many forums have you posted this on. It seems you are getting the same answer from all.....

BigBlack
10-29-2008, 06:24 PM
BB, How many forums have you posted this on. It seems you are getting the same answer from all.....

I admit I am a knowledge junkie and am a member of several boards. I am getting both sides of the fence but with good reasonings behind each and have learned so much in the last half day.

david dumas
10-29-2008, 09:16 PM
big,,,,, who cares how fast your bullet is going when it miss's it's target?? go for accuracy and no pressure signs,,,,,, chrony speed is like "et' in drag racing, its just something to brag about, most shooters don't care if your STW is 3200 ft/sec or 3800 ft/sec,,,,,,,,unless your trying to tune in a window, toss the chroney,,,,,,

the wind is my friend,,,,,,,,,,,,,,,,

DD

Boyd Allen
10-29-2008, 09:45 PM
For more than one accurate caliber it has been reported that accurate loads happen at more than one velocity with less accuracy between those velocities. These velocities that tend to produce accuracy are sometimes referred to as nodes. Many times reloaders find one node and as they try a little more or less powder notice that accuracy declines. At this point they stop extending from that point. In some cases, if they had continued on they would have found another accuracy above or below the first. Obviously pressure limits how high one can look.

Do your velocity/pressure over flags, on one target. Shoot your very best on a day when the wind is being kind. You may learn more than you had planned, and depending on your case size, you might want to use smaller steps, like say a third of a grain.

HovisKM
10-30-2008, 07:32 AM
What type of rifle are you shooting? Factory hunting, BR, varmit?? I am going to assume that you are shooting a hunting rifle. Here is where I believe velocity is more important....for the simple reason...if you shoot at a lower node....use a smaller cartriage. Why have a big old round with little powder....what you will find is if you shoot enough of those loads in three shot groups in hunting temps...they will go wild as the temp drops. Load density is important with hunting rounds also. However, only shoot what is safe. For example...I love the 270win, but if my rifle doesn't shoot well between 3000 and 3100fps with a 130gr bullet...I'm either looking for a different rifle or fixing the problem. I have only ever had one 270 that showed pressure sign before 3000fps and it went down the road.

One example with varmit rifles, I have a friend that loves the 220 swift...he swears by them. I perfer the 22-250 in factory rifles. We were shooting one day and I was outshooting him by just a little but what opened his eyes was when I got the chrono out and I was actually shooting 200fps faster than what he was. I asked him "so what's the use in the swift"? And I didn't have to fight with cases and other things that haunt the swift. I have nothing against the swift but if your going to use it....use it for what it's worth is...velocity.

Hovis

BigBlack
10-30-2008, 07:15 PM
Factory and will be used for hunting. I would like to keep velocity up so the trajectory is flatter.

Mr. D
10-31-2008, 12:04 AM
Field accuracy loading is my passion. Follow the recommendations of benchrest shooters in all ways. That's why I'm here. In most cases I have found that the most accurate loads will be nearly a full case of powder, so the powder you choose should be progressive enough to come close to a full case with acceptable pressures of course. Secondly, the best load will usually be found going up towards maximum SAFE pressure and then backing off in one to two tenth increments until you hit a sweet spot with a particular combination of components. Too low pressure is less dangerous, but just as bad for accuracy. For varminting, I believe in lighter bullets at faster speeds because time in flight is a big deal at long ranges with little moving pests! I don't like overbore cartridges because the benefit at 250+ yards is not that great and who wants to burn up the throat in a barrel that shoots like a dream. A 223 or 6mm will hit more than my shooting skills will allow. Most of my misses are wind, mirage or "operator error"! The last one is the big problem! :D

One more thing, buy an accurate rifle. I put 5 different loads with different bullet weights and three were factory loads in my Sako .223 and it shot 1/2" at 100 yds. Some guns shoot and others don't!

mikecyr
10-31-2008, 05:39 AM
If you happen to find a load whose velocity you like but is only a step away from shooting as accurately as you'd like, try tweaking the seated bullet depth. Sometimes this will improve accuracy. I will do this by bringing a single stage press to the range with me and shorten previously loaded rounds a few thousandths at a time looking for the sweet spot. Watch for pressure signs while doing this too. Being seated "into the lands" can raise starting pressure.

Keep your powder dry!


Mike