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In full disclosure while I have been reloading for a few years- this is my first attempt to load with very little data I cobbled together.
Rifle is a Kimber 8400 Tactical in .308.
I had a hard time finding reliable load data for 155gr Scenars and RL-15. So I averaged a few numbers I did find, and started a few grains lower at 41gr and loaded 15 rounds of each increasing up to 44grains- all kissing the lands. Had the opportunity to shoot at 200 yards and over a Chrony last weekend and gave it a go. 41gr was giving me the most accurate groups, followed by 43. 42 and 44 opened up a bit. With 41gr I was getting approx 2500 fps, which from what I have read is very slow. Seems most people shooting 155's are looking for speed more closer to 3k. I have read that if you use too little powder you can increase pressure, which judging by the visual brass inspection, I believe I was safe. Should I just go with the slower load or search for more accuracy with faster speeds?
This won't be for huniting, just target shooting out to 600 yards.
Last edited by robertham1; 07/01/16.
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41 grains @200 ![[Linked Image]](http://i670.photobucket.com/albums/vv70/robertham1/9EF4928C-6405-4202-BF87-0BEE3B66355E_zpscyngs0ud.png) 42 grains @ 200 ![[Linked Image]](http://i670.photobucket.com/albums/vv70/robertham1/70933A18-E65A-43C4-ADD6-5A5F8F91A1AA_zpst2syqq7n.png) 43gr @ 200 ![[Linked Image]](http://i670.photobucket.com/albums/vv70/robertham1/A794D40C-46DA-4C2D-A192-84C4425E52EE_zpsr5aua86l.jpg)
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I should also say that with 44gr of RL-15 I was getting approx 2700fps still with no signs of pressure.
I have since found more people loading this same combo up to 47gr- which gives me confidence in the higher end of the spectrum.
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Seat your bullet in 20-30 thousands and see how it shoots.Seating a bullet touching the lands can have a big effect on velocity and pressure.It can be like adding a grain or two of powder.This link from Hornady will explain this. http://www.hornady.com/ballistics-resource/internal
~Molɔ̀ːn Labé Skýla~
As Bob Hagel would say"You should not use a rifle that will kill an animal when everything goes right; you should use one that will do the job when everything goes wrong."Good words of wisdom...............
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I use to be all about speed, don't get me wrong I still like it, but I have never heard anyone brag about how fast they missed something.
I will take accuracy anyday
I may not be smart but I can lift heavy objects
I have a shotgun so I have no need for a 30-06.....
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This won't be for huniting, just target shooting out to 600 yards.
The above statement makes this a no-brainer. Paper doesn't care nor is it impressed with how fast the hole is made. Neither is anyone else worried about how fast hole in paper are made. Take your 41 grain load and start tweaking OAL until you have the best it will give you and then go and make itty-bitty groups on paper and forget speed entirely. I have a .270 that shoot tiny groups with 4350 and 110 grain TTSXs at 3170. Well below what it's capable of speed wise, but well more than enough to kill Bambi. I've killed about ten deer with the rifle and I haven't heard a one of them say they wished that it was a 3400 FPS load
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Campfire 'Bwana
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In full disclosure while I have been reloading for a few years- this is my first attempt to load with very little data I cobbled together.
Rifle is a Kimber 8400 Tactical in .308.
I had a hard time finding reliable load data for 155gr Scenars and RL-15. So I averaged a few numbers I did find, and started a few grains lower at 41gr and loaded 15 rounds of each increasing up to 44grains- all kissing the lands. Had the opportunity to shoot at 200 yards and over a Chrony last weekend and gave it a go. 41gr was giving me the most accurate groups, followed by 43. 42 and 44 opened up a bit. With 41gr I was getting approx 2500 fps, which from what I have read is very slow. Seems most people shooting 155's are looking for speed more closer to 3k. I have read that if you use too little powder you can increase pressure, which judging by the visual brass inspection, I believe I was safe. Should I just go with the slower load or search for more accuracy with faster speeds?
This won't be for huniting, just target shooting out to 600 yards.
First off, 3000 fps with a 155 is a figure more closely associated with Palma type barrels of 28" to 30" in length, and if I remember the model correctly your rifle has a 24" barrel. What brass are you using? The capacity varies a bit from one brand to the next and this will affect the charges you need to use. Assuming you're using Lapua brass you've got some charge weight headroom left. In fact you'll probably come into tune near 46 grains. Follow the link and scroll down to the chart. http://www.accurateshooter.com/cartridge-guides/308win/If you're using light WW brass you'll need a little more powder, heavy LC or FC will want a bit less. Oh yeah, you don't need to load fifteen at each charge increment.
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I have to agree about the brass.I tested the same load 45.5grs of Varget using a 165gr bullet with Winchester,Nosler and Remington brass in my 308.The Winchester and Nosler grouped the same,however the Remington brass loads grouped a noticeable one inch larger groups.
~Molɔ̀ːn Labé Skýla~
As Bob Hagel would say"You should not use a rifle that will kill an animal when everything goes right; you should use one that will do the job when everything goes wrong."Good words of wisdom...............
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I'd keep going up until you hit 2850-2900fps, or about 47gr, or until you see traditional pressure signs, and see if you get into a higher node. If not, it's no big thing to back down and work with the 43 or 41gr load.
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I'd keep going up until you hit 2850-2900fps, or about 47gr, or until you see traditional pressure signs, and see if you get into a higher node. If not, it's no big thing to back down and work with the 43 or 41gr load. That's what I would be inclined to try. While speed doesn't trump accuracy, it will give you less wind drift at 600yds.
I am continually astounded at how quickly people make up their minds on little evidence or none at all.
Jack O'Connor
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I'd keep going up until you hit 2850-2900fps, or about 47gr, or until you see traditional pressure signs, and see if you get into a higher node. If not, it's no big thing to back down and work with the 43 or 41gr load. That's what I would be inclined to try. While speed doesn't trump accuracy, it will give you less wind drift at 600yds. This. Find the next node.
You didn't use logic or reason to get into this opinion, I cannot use logic or reason to get you out of it.
You cannot over estimate the unimportance of nearly everything. John Maxwell
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Thanks for the responses.
I kinda pulled 3k out of my ass- the specific numbers people seemed to be happy with reaching were in the 2850-2900 range. I rounded up.
This is Hornady match brass.
I know I don't need 15 of each, but I wanted to shoot the entire afternoon, and I like to shoot three 5 shot groups to verify a load.
I think I'll continue to increase the powder as more knowledge doesn't hurt. I can always drop back down to 41/43.
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I agree with all those comments. With such a light load, you're probably running around 43000 psi (estimate via QuickLOAD) and you're probably getting around a 92% burn. Rifle powders work better when they are operated nearer to typical max pressures, like around 60000 psi or higher, depending on powder chemistry. My theory is that the closer to a 100% burn you achieve, the more consistent the burn will be from shot to shot. Whether or not that is correct, I have found that lighter loads of slower burning powders just don't perform as well.
You may be leaving quite a bit of performance on the table. I'd push on, with due caution of course. You can always pull the plug on increased charges if you see stuff you don't like.
Don't be the darkness.
America will perish while those who should be standing guard are satisfying their lusts.
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Sorry, I took too long to compose my comment and when I finally submitted it, your last post was there.
Don't be the darkness.
America will perish while those who should be standing guard are satisfying their lusts.
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Thanks for the responses.
I kinda pulled 3k out of my ass- the specific numbers people seemed to be happy with reaching were in the 2850-2900 range. I rounded up.
This is Hornady match brass.
I know I don't need 15 of each, but I wanted to shoot the entire afternoon, and I like to shoot three 5 shot groups to verify a load.
I think I'll continue to increase the powder as more knowledge doesn't hurt. I can always drop back down to 41/43. Hornady match has more room in it than the Lapua in the load I referenced. You have quite a bit of headroom left. Proceed upward with confidence.
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