308 Match Load development: How many grains should I increase per test?

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adrenaline681

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This is my first time doing match load development and I would like to start with Hornady 150gr FMJ-BT and IMR-4895 for my Tikka Bolt action.

In the Hornady book, it says for this bullet:

37.7 gr = 2300 fps
39.5 gr = 2400 fps
41.2 gr = 2500 fps
43.0 gr = 2600 fps
44.7 gr = 2700 fps
46.4 gr = 2800 fps

It seems quite a big range of loads (9gr spread). After doing some research I saw that most factory ammo for 308 are between 2600 fps and 2800 fps (150gr-168gr).

So I thought I could do my first shooting 2 groups of 5 bullets each per test using 0.5 gr increments:
43.0 gr
43.5 gr
44.0 gr
44.5 gr
45.0 gr

Would this be a good way to start or should I approach this in a different way? Should I try a wider range first instead (42gr, 43gr, 44gr, 45gr, 46gr) and then try to narrow it down?


Many thanks!
 
adrenaline681 said:
This is my first time doing match load development and I would like to start with Hornady 150gr FMJ-BT and IMR-4895 for my Tikka Bolt action.

In the Hornady book, it says for this bullet:

37.7 gr = 2300 fps
39.5 gr = 2400 fps
41.2 gr = 2500 fps
43.0 gr = 2600 fps
44.7 gr = 2700 fps
46.4 gr = 2800 fps

It seems quite a big range of loads (9gr spread). After doing some research I saw that most factory ammo for 308 are between 2600 fps and 2800 fps (150gr-168gr).

So I thought I could do my first shooting 2 groups of 5 bullets each per test using 0.5 gr increments:
43.0 gr
43.5 gr
44.0 gr
44.5 gr
45.0 gr

Would this be a good way to start or should I approach this in a different way? Should I try a wider range first instead (42gr, 43gr, 44gr, 45gr, 46gr) and then try to narrow it down?


Many thanks!
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When I'm chasing groups I'd start off by weighting each bullet and separating them in their own weight category then start with 0.5 gr increments then 0.1 gr and double checked each load with a balance beam and a good digital scale.
 
I usually just do .2 grain increments. I usually only load 2-3 but what I do it to make sure to shoot all of them on identical targets and compare the vertical change in the loads. Look for a an area that has good groups and a window where the vertical is not changing. For example you may find a 43.3 to 43.9 all shoot well and are on the same vertical plane. I will now do larger tests 5 or 10 with smaller powder charges to find the tightest inside that range and may also adjust OAL in there as well. I usually do this at 300 or 400m. At a 100 it can be done but with a really accurate gun things may not show up you will see farther out.
 
Your smallest group with a FMJ-BT bullets might be 2 or more inches. Or you could just start with a match bullet and not waste your time, powder and barrel life. But you never know, maybe your rifle will be the exception any print FMJ-BT bullets with benchrest accuracy.
 
Seriously , just start with the SMK's.

They aren't that expensive. half the price of premium hunting bullets.

As for charge weights, start at or just below the lowest published weight you can find, you are going for accuracy not speed.
 
Kelly Timoffee said:
Seriously , just start with the SMK's.

They aren't that expensive. half the price of premium hunting bullets.

As for charge weights, start at or just below the lowest published weight you can find, you are going for accuracy not speed.
Click to expand...

Agreed, you're just wasting time and components using cheap bullets and when it comes time to start loading for the SMK's you're just going to have to start all over again. Plus I can guarantee once you start producing better shots you'll abandon the 150 cheapo's right then and there. If you're going to spend all this time and money on the gun, why cheap out on one of the more critical components?

I did the same as you though. Initial testing of .5gr increments from minimum to maximum record and observe. Now I'm going to load .1gr increments in the areas that grouped the best and go from there. I'm personally not going to weigh bullets and go that far down the rabbit hole simply because that exceeds my abilities as a shooter.
 
When ever I do a load work up, I will take Max load and minus 10% and start there. I will move in 0.3 incerments and once I find an area I will do those in 0.1 to find the best spot. Then I will play with seating depth.
I also agree with the others, don't waste time and funds doing this with a cheaper bullet. All my rifles so far shoot the Lapuas scenars the best with the SMK right behind them.
 
Your component choice is what i use for plinking. 42.2 gr imr 4895 with a hornady 150 fmjbt shoots 1-2" out of all my .308's .

If you want a match load, try 155 lapua or sierra or step up to 168's or heavier.... but depending on your twist rate of course.7
 
Poor choice of bullet. If you want to load that bullet, just load it with 44 gr of 4895 and plink away.

The cost of your "load development" would be better invested in better bullets.

The sierra 155 match is an excellent suggestion.

About 40 years ago I was considering the Hornady 150 FMJ as an accurate practice bullet to save money. I phoned Hornady (Joyce, the owner) and asked him about the idea.

He said the FMJ is the least accurate bullet they make, because it is open at the base. he said any of their soft points would be much more accurate.

I bought 20,000 of the 150 SP BT bullets and 20,000 of the 165 SPBT. he was right. They are cheap and almost as accurate as match bullets to 500 yards.

I still have some of them and shoot them when I want an accurate cheap round.
 
BTW, a cheap accurate bullet good for up to 200 yards is the Sierra 125 SP. It is sometimes used by Americans competing at the 200 yard rapid fire match.

I saw them doing this; bought some and tried them. MOA was easy.
 
adrenaline681 said:
True, but I want to find a budget load that will get me the smallest groups as possible. after that i will switch to Sierra Match Kings and see how much tighter groups i can get.
Click to expand...

If that is your plan, the prudent thing to do there would be to start all over, unless you use teh same weight bullet. In that case, you'll still end up doing probably 2/3 of the testing again.....
 
I'll often go up a grain per shot just to find a working maximum. After that I can work down if I need to, or quit if the speed isn't there. That applies more to big barrel eating cases than mild things like a .308.
 
todbartell said:
I run 1% increments for all cartridges. In a 308, 0.4gr steps
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Thanks everyone for the info, I already bought some time ago 1000 Hornady FMJBT bullets to learn how to shoot 308 and might as well try to get the best load for them.

Since I cant visit the range very often since its 1 and half hours away from where live, I will do 11 test groups (5 round groups) and each test group I will shoot it twice to confirm consistency.
I will also try to cool my barrel to the same temperature after each group so they all start from the same temp. I will shoot first from low charge to high charge to make sure there are no signs of pressure, then I will clean the barrel then do the second set of groups from high charge to low charge to try to avoid any accuracy deviation due to dirty barrel.

I will try to cool the barrel using a home made version of the "Chamber Chiller" that I will build this week for 20 bucks or so and measuring the barrel temperature with a laser thermometer:
Chamber-Chiller-BETA-60-v1.40-Prototype-Design-600x467.jpg



Hopefully I can find something that will have a decent accuracy for my plinking rounds. And will be a good learning experience to prepare me to load more accurate rounds like Sierra Match Kings.

These will be my testing loads at 2.700" OAL:
41.0 gr
41.5 gr
42.0 gr
42.5 gr
43.0 gr
43.5 gr
44.0 gr
44.5 gr
45.0 gr
45.5 gr
46.0 gr
 
Last edited:
308 win Loads that work

Lots of talk on loads with 150 to 155gr bullets in .308 win with Hornady bullets and Sierra MK have two friends shooting 308s one using 155 gr MK 2155 with lots of Varget watched HIM SHOOTING AT 100 Y .155" AND 300 Y .710"
Target below was shot at 300 y 6 shots using lots Varget and 155.5 Bergers and this was shot and witnessed using no scope, Warner Tool and die peep sights.
So save your barrel life and use Bergers or Sierras
really no one in winners circle in F class use Hornady bullets

View attachment 193716
 
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