308 load development questions

[ReedTX]

Over the weekend I went out and shot some more groups with my 308. I am looking for guidance on what to do next. These were some of my first reloads having only taken up the hobby a few months ago. Here is what I am using

Powder : BLC-2
Projectile : Hornady 150gr Interlock BTSP

I cannot find anywhere that lists Hornady bullets and Hodgson powder together. Hodgsons website tells me that the max load is 46g. My starting load was -10% so 41.4g and I tested loads in +0.5g increments up to 43.9g. I noticed the slightly hotter rounds shot slightly better groups, but not by a significant amount. I did notice my POI did shift upwards but I think this is to be expected with increased velocity.

I would like to load some more at 44.4g, 44.9g and so on in 0.5g increments to try those out too. The thing that worries me is that the load data for the bullets I am using show the max limit to be anywhere from approx 47g to even 52g dependent on the powder (my powder is not listed in the Hornaday manual).

What would be a 'safe' stopping point/max load for my powder & bullet combo. I understand there may be better powders, but this is all I have access too right now so need to stick with it.

I am a beginner. So please go easy!

I am trimming to 2.005 and my case length is 2.735 in accordance with the Hornady manual

 

[jmr40]

I can't help with that powder since I've never used it, but you're on the right track by asking questions. Every load I've ever used has been "borrowed" from others. I would never blindly try a load offered on the internet, but If I could find data for that powder and bullet weight, I'd use that as a starting point. If you find that a number of shooters are having good luck with 44-45 gr of powder X with brand Y 150 gr bullet, chances are good you'll have good luck too.

If you can't find the exact bullet listed with a specific powder it is generally OK to choose a very similar bullet in the same weight. You're going to start low and work up anyway. You may find that the max load is slightly different, but you'll know that when you get there. The load data for solid copper bullets is much different than for conventional bullets in the same weight. Unless you're using those most any other 150 gr bullet is going to be close enough for starting loads.

 

[redcon1]

You could always pick a different bullet which might actually be a good idea since you're just starting out. You can use load data for other 150 gr bullets but, as a beginner, maybe you'd be better off with a different bullet like the one you have solid data for. I'm looking at the Hodgdon site and it shows a Nosler 150 gr BT having a start charge of 45 gr and a max charge of 48 gr. If you're determined to use a bullet that you can't find data for, then I would definitely start at the bottom and work up. The brass you're using also matters. If you're using Lake City brass, you're supposed to reduce your start charge by 1 grain according to some or 5% according to others. That always complicates things. I have a bunch of WC846 which is the military equivalent of BLC2 and it says it's a fast lot on the jugs and you should reduce your start load by a further 5% so now finding a start load gets even trickier. And you're developing a load in the spring time which will undoubtedly be fired in the Texas summer months which, as I remember, were normally well above 100 degrees. BLC2 is not known for being temperature stable and a near max load worked up in the spring and left out in the sun in the Texas summer could be a problem. For more load data, I recommend a monthly subscription to loaddata.com especially until you have a few established safe and accurate loads and maybe a book or two or three. For .308, BTW, I can't recommend Varget and the 168 gr AMAX highly enough. Varget is one of the top picks for Benchrest shooters and it is very temperature stable which would be a blessing in Texas. The 168 gr AMAX always shoots very well for me but that's my gun and barrel so...

 

[horsey300]

Over the weekend I went out and shot some more groups with my 308. I am looking for guidance on what to do next. These were some of my first reloads having only taken up the hobby a few months ago. Here is what I am using

Powder : BLC-2
Projectile : Hornady 150gr Interlock BTSP

I cannot find anywhere that lists Hornady bullets and Hodgson powder together. Hodgsons website tells me that the max load is 46g. My starting load was -10% so 41.4g and I tested loads in +0.5g increments up to 43.9g. I noticed the slightly hotter rounds shot slightly better groups, but not by a significant amount. I did notice my POI did shift upwards but I think this is to be expected with increased velocity.

I would like to load some more at 44.4g, 44.9g and so on in 0.5g increments to try those out too. The thing that worries me is that the load data for the bullets I am using show the max limit to be anywhere from approx 47g to even 52g dependent on the powder (my powder is not listed in the Hornaday manual).

What would be a 'safe' stopping point/max load for my powder & bullet combo. I understand there may be better powders, but this is all I have access too right now so need to stick with it.

I am a beginner. So please go easy!

I am trimming to 2.005 and my case length is 2.735 in accordance with the Hornady manual

Hodgdon shows 45-48 min max for bl-c 2 min max with a 150 nbt, use that data, start at 45 and work slow up.

 

[Blue68f100]

Over the weekend I went out and shot some more groups with my 308. I am looking for guidance on what to do next. These were some of my first reloads having only taken up the hobby a few months ago. Here is what I am using

Powder : BLC-2
Projectile : Hornady 150gr Interlock BTSP

I cannot find anywhere that lists Hornady bullets and Hodgson powder together. Hodgsons website tells me that the max load is 46g. My starting load was -10% so 41.4g and I tested loads in +0.5g increments up to 43.9g. I noticed the slightly hotter rounds shot slightly better groups, but not by a significant amount. I did notice my POI did shift upwards but I think this is to be expected with increased velocity.

I would like to load some more at 44.4g, 44.9g and so on in 0.5g increments to try those out too. The thing that worries me is that the load data for the bullets I am using show the max limit to be anywhere from approx 47g to even 52g dependent on the powder (my powder is not listed in the Hornaday manual).

What would be a 'safe' stopping point/max load for my powder & bullet combo. I understand there may be better powders, but this is all I have access too right now so need to stick with it.

I am a beginner. So please go easy!

I am trimming to 2.005 and my case length is 2.735 in accordance with the Hornady manual

Have you checked to see how much bullet jump you have in your gun?

Are you getting a sticking bolt lift after firing?

Any HP signs, case head flattening, primers ,which are not a reliable.

Do you have a crony to run your loads over?

Just remember that load data is just a guide reporting on what they got, that day, in there equipment. With their lot of powder/primer/bullet. Your results will likely be different.

 

[bullseye308]

There is data out there to find, I don’t have any handy as I’m not loading 308 anymore. What other powders and or bullets are available to you hopefully locally. It’s not that there isn’t a good combination with what you have, just the data is more limited. If you could get us a list of what other powders you have access to as well as bullets, we could help you start off a little easier with a more popular combination.

It’s frustrating this day and age to be starting out with the limited supplies and availability, we understand the challenges that go with it. If you can’t find other powders or bullets to try I’m sure someone here will have that info or be able to point you to it. Welcome to the wonderful world of reloading.

 

[Howa 9700]

Hodgdon shows 45-48 min max for bl-c 2 min max with a 150 nbt, use that data, start at 45 and work slow up.

Lee reloading manual also shows 45-48 as start and max for bl-c 2 for 150 grain jacketed bullet, which OP's Hornady is.

As an aside, it seems to me that the load data in Hornady manual is on the conservative side. Can't remember which one but one load I found in the Hornady book had the max load almost the same as the start load in Hodgdon, Lee or both. It has been another observation of mine that the powders listed in the Hornady book tend to be limited in scope, but are also the "all stars" for that caliber. If the OP wants to expand his horizons......he could keep an eye out for some of those......like a 4064, 4895 or even Varget. Remarkably, Varget has been showing up now and then.

 

[bullseye308]

If you could put hands on some Varget, it would be hard not to make a good load.

 

[mkl]

As a new reloader have you read up on "barrel harmonics" yet? A rifle barrel will vibrate up, down, and sideways as the bullet passes through under the high pressure of the burning gases of your powder. Your best groups will happen when the barrel is at exactly the same place after every shot. That is a function of several things including bullet type, pressure curve, etc. When varying the powder weights and the type of powder itself, you are trying to find that magic point where the barrel harmonics align at exactly the same spot as the bullet exits the muzzle of your rifle. This point seldom occurs at near maximum loads or with case fill less than 90+ percent. Every rifle is different; you just have to experiment to find the powder and weight that gives you a barrel harmonic that produces the smallest group size.

Were I to have only one powder, I would drop about 10% below the suggested minimum and work up slowly (say 0.3 grains) to about 95% of what the books suggest as maximum. Should you not get an acceptable grouping, then BC2 will not give a pressure curve that will produce the best harmonic in your barrel and you need to try another powder.

Don't mean to get too technical, but if you check out "barrel harmonics" on this forum or google you can get an idea of the subject as it applies to accuracy.

 

[ReedTX]

Have you checked to see how much bullet jump you have in your gun?

Are you getting a sticking bolt lift after firing?
No

Any HP signs, case head flattening, primers ,which are not a reliable.
No flattened primers from what I can gather

Do you have a crony to run your loads over?
No I do not. I am on the lookout for one though, if you have any budget friendly mid-range recommendations I will certainly add them to my wish list

Just remember that load data is just a guide reporting on what they got, that day, in there equipment. With their lot of powder/primer/bullet. Your results will likely be different.

Thank you for your post and guidance.

edit : i have added my answers to your questions within the quote body.

 

[ReedTX]

If you could put hands on some Varget, it would be hard not to make a good load.

I am constantly on the look out on the reddit reloading discord and in local stores. Right now all I have is the BLC-2, I am enjoying my reloading though even though it is not an ideal powder or one that is recommended much. I bought it because it the only one I could get in Cabelas at the time and it had .308 data. Same deal with the projectiles.

 

[AJC1]

Keeping things as simple as possible review what pressure signs are and what they look like. Reading primers is not hard and bolt lift is not crazy hard to figure out. Consider its getting warmer every day an a 10 degree increase can matter a lot.

 

[ReedTX]

As a new reloader have you read up on "barrel harmonics" yet? A rifle barrel will vibrate up, down, and sideways as the bullet passes through under the high pressure of the burning gases of your powder. Your best groups will happen when the barrel is at exactly the same place after every shot. That is a function of several things including bullet type, pressure curve, etc. When varying the powder weights and the type of powder itself, you are trying to find that magic point where the barrel harmonics align at exactly the same spot as the bullet exits the muzzle of your rifle. This point seldom occurs at near maximum loads or with case fill less than 90+ percent. Every rifle is different; you just have to experiment to find the powder and weight that gives you a barrel harmonic that produces the smallest group size.

Were I to have only one powder, I would drop about 10% below the suggested minimum and work up slowly (say 0.3 grains) to about 95% of what the books suggest as maximum. Should you not get an acceptable grouping, then BC2 will not give a pressure curve that will produce the best harmonic in your barrel and you need to try another powder.

Don't mean to get too technical, but if you check out "barrel harmonics" on this forum or google you can get an idea of the subject as it applies to accuracy.

I do have a (very) brief understanding of barrel harmonics. Your explanation is great, thank you for taking the time to write it for me and other beginner reloaders

 

[horsey300]

Lee reloading manual also shows 45-48 as start and max for bl-c 2 for 150 grain jacketed bullet, which OP's Hornady is.

As an aside, it seems to me that the load data in Hornady manual is on the conservative side. Can't remember which one but one load I found in the Hornady book had the max load almost the same as the start load in Hodgdon, Lee or both. It has been another observation of mine that the powders listed in the Hornady book tend to be limited in scope, but are also the "all stars" for that caliber. If the OP wants to expand his horizons......he could keep an eye out for some of those......like a 4064, 4895 or even Varget. Remarkably, Varget has been showing up now and then.

Lee just stole hodgdon, Lee does none of their own data, just copy and paste from the other published sources, so that makes sense.

 

[horsey300]

I am constantly on the look out on the reddit reloading discord and in local stores. Right now all I have is the BLC-2, I am enjoying my reloading though even though it is not an ideal powder or one that is recommended much. I bought it because it the only one I could get in Cabelas at the time and it had .308 data. Same deal with the projectiles.

Those projectiles should be just dandy, don't sweat it.