OAL vs. Accuracy
- Thread starter waynewjw
- Start date
waynewjw
CGN Regular
Pretty Much
That'll do it. Again looks easy, but I've found the bullet to slide either into the cartridge or stick in the lands and pull out, so one has to be careful. I will try this next against the dowel technique and see what difference in OAL.
That'll do it. Again looks easy, but I've found the bullet to slide either into the cartridge or stick in the lands and pull out, so one has to be careful. I will try this next against the dowel technique and see what difference in OAL.
The method used in the video will work but at least one thing he stated is false. He tells you not to seat into the lands, lots of target shooters do this for the most accurate load. It can be a problem for a hunter if the bullet happens to stick and you go to unload an unfired round. Lots of different ways to skin a cat, some are easier some more precise. It all depends on your skill as a shooter and equipment if you can see the difference in seating depth and other reloading tricks.
I don't imagine you want to seat into the lands if you've charged a max powder load. AFAIK if you do that you could cause some 'too high' pressure issues. But if you use the method in the video of finding the best possible seating depth and then work up your powder load - if the optimal OAL is touching the rifling, the so be it. The only time I ever use this method is to load hunting rounds so I definitely don't want to engage the rifling for the same reason Dead Meat mentioned:
As always, others' mileage will most definitely vary. There's many opinions and just as many ways of doing things.
As always, others' mileage will most definitely vary. There's many opinions and just as many ways of doing things.
waynewjw
CGN Regular
OAL For Best Results
Although I want to achieve superb accuracy at the range; best described as minimally 3 rounds touching/cloverleaf, in the end what I want is the most accurate hunting round I can get.
So what I've derived from all the great posts is deal with the OAL first, then work the powder and load for even greater accuracy from there.
So yesterday I went to the range and had (2) different bullet types in 180 grain - Sierra Game Kings in Spitzer BT and Nosler Accubond in Spitzer. The Sierra were in a range of OAL (book is 3.34", if memory serves me) however, using the dowel confirmation program I started at 3.32" and decreased in 30 thou increments. The results weren't very exciting with the best 4-shot group around 1". The Nosler's were all the same length 3.282" and different IMR4350 powder loads starting at 55 grains, then 55.3/55.5/55.7 and 56. So the best group was around 3/4", acceptable for a hunting load....but.....I still think I'm out on the OAL. So later today, I will use several of the methods described above and see if I can tighten up the results. From there, I will use one powder load, back off each successive 3-cartridge set by 30 thou and see what results that will bring.
Unfortunately, with the great wet weather predicted for the next week or so, not sure when I'll be able to get out and do some range testing.
Although I want to achieve superb accuracy at the range; best described as minimally 3 rounds touching/cloverleaf, in the end what I want is the most accurate hunting round I can get.
So what I've derived from all the great posts is deal with the OAL first, then work the powder and load for even greater accuracy from there.
So yesterday I went to the range and had (2) different bullet types in 180 grain - Sierra Game Kings in Spitzer BT and Nosler Accubond in Spitzer. The Sierra were in a range of OAL (book is 3.34", if memory serves me) however, using the dowel confirmation program I started at 3.32" and decreased in 30 thou increments. The results weren't very exciting with the best 4-shot group around 1". The Nosler's were all the same length 3.282" and different IMR4350 powder loads starting at 55 grains, then 55.3/55.5/55.7 and 56. So the best group was around 3/4", acceptable for a hunting load....but.....I still think I'm out on the OAL. So later today, I will use several of the methods described above and see if I can tighten up the results. From there, I will use one powder load, back off each successive 3-cartridge set by 30 thou and see what results that will bring.
Unfortunately, with the great wet weather predicted for the next week or so, not sure when I'll be able to get out and do some range testing.
waynewjw
CGN Regular
New OAL
So, checked the OAL to the lands for both bullet types and came up with some interesting results, considerably different that I had posted earlier.
The Sierra Game Kings were 3.28 and the Nosler Accubonds were 3.32. So I will do some load development starting 30 thous back of these measurements and see what accuracy results I get.
So, checked the OAL to the lands for both bullet types and came up with some interesting results, considerably different that I had posted earlier.
The Sierra Game Kings were 3.28 and the Nosler Accubonds were 3.32. So I will do some load development starting 30 thous back of these measurements and see what accuracy results I get.
Yeah it'll definitely change from bullet to bullet because of their different shapes. One that is long and tapers in gently will have to be seated farther out giving a longer OAL than let's say a hollow point or a RN that will bu much more broad for most of the length of the bullet because it will engage the rifling much closer to the tip of the bullet.
One size definitely does not fit all.
One size definitely does not fit all.
waynewjw
CGN Regular
So I backed of the powder by 0.5 gns. and decided to do up another batch. Got 12 rounds in the Sierra's but ran out of powder, so production has been halted till I pickup more IMR4350 powder, which should be in the next couple of days, I hope.
I started the Sierra back 3/1000's and did 3 rounds, then backed off another 3 thousandths, so I've got 4 rounds, one right at the lands, and 3 sets back off.
Plan to do the same with the Nosler's once I get more powder.
I started the Sierra back 3/1000's and did 3 rounds, then backed off another 3 thousandths, so I've got 4 rounds, one right at the lands, and 3 sets back off.
Plan to do the same with the Nosler's once I get more powder.
waynewjw
CGN Regular
OAL Results
So a week of wet weather, and some measuring and loading. Determined that OAL touching the lands in the 30-06 for the Sierra 180 Gn. Spitzer was 3.280. I did 3 cartridges in each length starting at 3.280, 3.277, 3.274 and 3.271 all with 55.5 grains of IMR4350. The groups ranged from 1.63" down to 1.4" however, I had two shots at 1/4" so I'm going with that OAL and will now set up some loads in 0.5 powder increments to see how tight I can get them.
On the Nosler's 180 Grn. Spitzer, the OAL touching the lands was 2.320, so I reduced again 3/1000's to 3.317, 3.314, 3.311. Same powder load. The groups using the Nosler Accubonds ranged from 3.41" to 2.20" with one 2-shot group at .29". With this group I definitely felt that the 3rd shot was my bad...so I'm going to see what I can develop from this setup. However, based on some of the holes, I felt like the bullet was perhaps tumbling, not clean cut holes like the Sierra's. Any idea what I doing that would cause that???
I probably should have loaded with more powder, as I could go all the way up to 60 grains, the rifle had a bit more jump than I would have liked. So much better groups than going with the manual standard recommended OAL.
And the trick, for me, in determining OAL to the lands, is to take a fired case and press down just slightly with the resizing die in, so that I can get the bullet to slide in and out but with some force. I had to try a half dozen to get one just right, and I used two cartridges x 2 setups to determine OAL.
The issue and determination of OAL has certainly become clearer in my mind, easier to determine now that I've tried a couple of different ways, and will move forward with other calibers to determine best results.
Cheers and thanks to everyone else who had valuable input.
So a week of wet weather, and some measuring and loading. Determined that OAL touching the lands in the 30-06 for the Sierra 180 Gn. Spitzer was 3.280. I did 3 cartridges in each length starting at 3.280, 3.277, 3.274 and 3.271 all with 55.5 grains of IMR4350. The groups ranged from 1.63" down to 1.4" however, I had two shots at 1/4" so I'm going with that OAL and will now set up some loads in 0.5 powder increments to see how tight I can get them.
On the Nosler's 180 Grn. Spitzer, the OAL touching the lands was 2.320, so I reduced again 3/1000's to 3.317, 3.314, 3.311. Same powder load. The groups using the Nosler Accubonds ranged from 3.41" to 2.20" with one 2-shot group at .29". With this group I definitely felt that the 3rd shot was my bad...so I'm going to see what I can develop from this setup. However, based on some of the holes, I felt like the bullet was perhaps tumbling, not clean cut holes like the Sierra's. Any idea what I doing that would cause that???
I probably should have loaded with more powder, as I could go all the way up to 60 grains, the rifle had a bit more jump than I would have liked. So much better groups than going with the manual standard recommended OAL.
And the trick, for me, in determining OAL to the lands, is to take a fired case and press down just slightly with the resizing die in, so that I can get the bullet to slide in and out but with some force. I had to try a half dozen to get one just right, and I used two cartridges x 2 setups to determine OAL.
The issue and determination of OAL has certainly become clearer in my mind, easier to determine now that I've tried a couple of different ways, and will move forward with other calibers to determine best results.
Cheers and thanks to everyone else who had valuable input.
