270 Win and H4831SC

[Fudd]

Merry Christmas Rokslide!

Recently got serious about learning to handload after collecting a fair amount of components, one of which is causing me to scratch my head.

I’m loading for a 22” tikka 270 and hoping to get a 130gr accubond dialed in. If you look up 130gr loads online or in manuals, inevitably H4831sc is mentioned as THE powder to try. Nosler has it as the most accurate load tested, and many many mentions on forums of it being the go-to.

Yet, when I plug this into Gordon’s with my actual measured h2o fired case capacity, the result is an unburnt propellant % in the 80s, implying it’s too slow. The tool implies that N160 and Hunter are much better fits, but they too will be under 100% burn. I suspect most 270s back in the day were 24” or 26” barrels using thinner brass, which helps H4831 but still never gets it up above 90% burn rate.

So my questions are these, am I overthinking it and should I just load a ladder with all three and see how it shakes out? Have you found GRT’s unburnt propellant parameter to be a good predictor of erratic loads, or do you prioritize something else? A 130gr bullet out of a 270 win isn’t exactly an obscure loading, so why does GRT imply you have to thread the needle?

 

[ResearchinStuff]

I messed around a lot with grt 2 years ago, then stopped. I haven't found a real use for it unless you're trying to do something not covered in a book. H4831sc is good stuff, shot it a lot in my 25/06.

 

[S-3 ranch]

I’m still loading 60.5 of 4831 in my win 70 featherweight ( 22inch) and getting
3160 & hunting accuracy
4350 with 150gr ( don’t remember the fps)

 

[Fudd]

I’m still loading 60.5 of 4831 in my win 70 featherweight ( 22inch) and getting
3160 & hunting accuracy
4350 with 150gr ( don’t remember the fps)

You are definitely not alone, there are countless mentions online of similar results. I’m just wondering why GRT disagrees, or actually if it even does. GRT doesn’t give a warning that 85% burn rate will cause an issue, or at least one that I’ve noticed, yet you’ll find folks proclaiming that anything less than 100% burn rate leads to erratic velocity.

 

[Steve O]

Wow, you are definitely overthinking it. I’d double check my scale with the known weights that come with it then go shoot the heck out of it. 4831 IS the powder for the 270. My 10 or so over the years have all loved one grain under max and 140g Btips and AccuBonds. Most use 130s but I’ve always preferred the 140s.

 

[SDHNTR]

I load the same powder in my .270 with fine results and don’t even know what GRT is, nor could I care less.

 

[Fudd]

Wow, you are definitely overthinking it. I’d double check my scale with the known weights that come with it then go shoot the heck out of it. 4831 IS the powder for the 270. My 10 or so over the years have all loved one grain under max and 140g Btips and AccuBonds. Most use 130s but I’ve always preferred the 140s.

I have 3lbs of H4831sc sitting next to me on the bench right now, so I wasn’t overthinking it so hard that I wasn’t gonna try it. I’m also not trying to shoot bug holes with this gun. More just trying to understand how GRT could have gone so off the rails with this one, or if I’m using it wrong.

 

[Steve O]

I’ve now got a Christmas project and that is to find out what the heck GRT is…4831 was, is, and forever more will be a great powder for .270 Win hunting weight bullets. If you are stuffing 55-60 grains of 4831 in there with a standard primer, you are good. GRT or not.

 

[slatebuilder]

Merry Christmas Rokslide!

Recently got serious about learning to handload after collecting a fair amount of components, one of which is causing me to scratch my head.

I’m loading for a 22” tikka 270 and hoping to get a 130gr accubond dialed in. If you look up 130gr loads online or in manuals, inevitably H4831sc is mentioned as THE powder to try. Nosler has it as the most accurate load tested, and many many mentions on forums of it being the go-to.

Yet, when I plug this into Gordon’s with my actual measured h2o fired case capacity, the result is an unburnt propellant % in the 80s, implying it’s too slow. The tool implies that N160 and Hunter are much better fits, but they too will be under 100% burn. I suspect most 270s back in the day were 24” or 26” barrels using thinner brass, which helps H4831 but still never gets it up above 90% burn rate.

So my questions are these, am I overthinking it and should I just load a ladder with all three and see how it shakes out? Have you found GRT’s unburnt propellant parameter to be a good predictor of erratic loads, or do you prioritize something else? A 130gr bullet out of a 270 win isn’t exactly an obscure loading, so why does GRT imply you have to thread the needle?

We tried some 4831SC and IMR 4831 in several 270s. Though it was with a different bullet than the 130 accubond, we ended up using either H4350, RL16, or IMR 4350 with 130’s through 150’s. The computer at is nice and everything, but let your target tell you which is best.

 

[S-3 ranch]

I’ve now got a Christmas project and that is to find out what the heck GRT is…4831 was, is, and forever more will be a great powder for .270 Win hunting weight bullets. If you are stuffing 55-60 grains of 4831 in there with a standard primer, you are good. GRT or not.

In reloading terms,
GRT stands for Gordon's Reloading Tool.
It is a free, open-source computer software program used for internal ballistic simulation. It is widely used by handloaders to predict pressures, velocities, and barrel harmonics without needing to physically fire as many test rounds.

It a B.S shortcut where you don’t have to go to the range to get field test
AI load work ?

 

[Fudd]

I’ve now got a Christmas project and that is to find out what the heck GRT is…4831 was, is, and forever more will be a great powder for .270 Win hunting weight bullets. If you are stuffing 55-60 grains of 4831 in there with a standard primer, you are good. GRT or not.

Gordon’s Reloading Tool - similar to quick load but free. It’s essentially a load book built off of shooters’ actual chrono measurements, so it’ll tell you how much you’re expected to lose with a shorter barrel, at higher or lower temp, etc. Two things (among many) it spits out are case fill % and what % powder is going unburned. MOST of the time it agrees with load books that the “pet” powder for a given cartridge/bullet is going to be one that almost fills the case and leaves little to no unburned powder, with a big exception being 270 win and H4831, it predicts you need to overfill the case before hitting pressure and that 15% of that is going out the bore unburned, or in other words the powder’s burn rate is way too slow.

 

[TaperPin]

Nothing wrong with over thinking things and geeking out on loading programs if you enjoy it. However, if one powder could be ideal, producing best groups across all, or even most rifles, that’s all any of us would use, but that’s not usually what we see in hunting guns. It’s fun to watch an influencer go through how they select powders and watch them make little groups, but before any of loading programs existed, those same influencers were still making small groups with loading manuals and trial and error.

It is good to understand burn rates and stick to powders in the normal range, but I don’t know that any rifle of mine had the same “most accurate load tested” published in a manual. It’s still a fun tidbit of trivia to know what shot well in the test gun.

Short cut powders never made sense to me since there isn’t a benefit to reloaders I can put a finger on. My guess is they were developed for factory ammo production and marketing them to reloaders gives a flooded category even more choices that aren’t needed. When the same powder company makes multiple versions of almost identical powders, I chalk it up to marketing. If it didn’t make them extra profit they wouldn’t do it. Something about human nature wants to believe there is a perfect solution.

Even though I’m not the target market for many of the new powders, it doesn’t mean someone shouldn’t try them if it makes your heart happy. At the range I enjoy making bets with friends if a newly released powder will group better than existing loads with traditional powders. lol

 

[Fudd]

Nothing wrong with over thinking things and geeking out on loading programs if you enjoy it. However, if one powder could be ideal, producing best groups across all, or even most rifles, that’s all any of us would use, but that’s not usually what we see in hunting guns. It’s fun to watch an influencer go through how they select powders and watch them make little groups, but before any of loading programs existed, those same influencers were still making small groups with loading manuals and trial and error.

It is good to understand burn rates and stick to powders in the normal range, but I don’t know that any rifle of mine had the same “most accurate load tested” published in a manual. It’s still a fun tidbit of trivia to know what shot well in the test gun.

Short cut powders never made sense to me since there isn’t a benefit to reloaders I can put a finger on. My guess is they were developed for factory ammo production and marketing them to reloaders gives a flooded category even more choices that aren’t needed. When the same powder company makes multiple versions of almost identical powders, I chalk it up to marketing. If it didn’t make them extra profit they wouldn’t do it. Something about human nature wants to believe there is a perfect solution.

Even though I’m not the target market for many of the new powders, it doesn’t mean someone shouldn’t try them if it makes your heart happy. At the range I enjoy making bets with friends if a newly released powder will group better than existing loads with traditional powders. lol

Thanks for the detailed and thoughtful reply.

I wouldn’t be reloading if I didn’t want to tinker with it, this gun shoots factory loaded partitions really well, but this gives me something to figure out.

My questions aren’t just for this gun or bullet, it’s more learning what sources to put a little more faith in. Everyone here turned to a page or asked a friend where to start with a given load, just too many options otherwise. Gordon’s is only as good as what people entered, and I’ve yet to find a manual that doesn’t milk a 24” barrel for all it’s worth.

 

[Steve O]

Thanks for the detailed and thoughtful reply.

I wouldn’t be reloading if I didn’t want to tinker with it, this gun shoots factory loaded partitions really well, but this gives me something to figure out.

My questions aren’t just for this gun or bullet, it’s more learning what sources to put a little more faith in. Everyone here turned to a page or asked a friend where to start with a given load, just too many options otherwise. Gordon’s is only as good as what people entered, and I’ve yet to find a manual that doesn’t milk a 24” barrel for all it’s worth.

Find some manuals from last century; you will be amazed at how throttled back today’s loads are. The manufacturers are very careful these days.

 

[6mm Remington]

I loaded 130 gr. Partitions for a friend's 270 Winchester. I used Federal 215 Magnum primers while working up the load for his rifle and they seemed to work very well. I believe it ended up being 59.0 grs of H4831SC for that load. I don't recall the velocity he got with it but there were no pressure signs and it shot great. Many elk were taken with that load.

 

[Fudd]

Find some manuals from last century; you will be amazed at how throttled back today’s loads are. The manufacturers are very careful these days.

This is why some people like GRT, it tells you pressure - sometimes showing safe loads above book max. At the end of the day it’s just another load book, but one built on what people have measured not just what Nosler’s lawyers would let them put down.

 

[SDHNTR]

Thanks for the detailed and thoughtful reply.

I wouldn’t be reloading if I didn’t want to tinker with it, this gun shoots factory loaded partitions really well, but this gives me something to figure out.

My questions aren’t just for this gun or bullet, it’s more learning what sources to put a little more faith in. Everyone here turned to a page or asked a friend where to start with a given load, just too many options otherwise. Gordon’s is only as good as what people entered, and I’ve yet to find a manual that doesn’t milk a 24” barrel for all it’s worth.

If you want a place to start use the reloading manual or published data for the bullet you want to use. No AI or brain busting needed.

 

[elkguide]

Only reloaded for 15 or so .270s over the years. Tried a lot of different powder and bullet combinations. If I couldn't get the speed and accuracy that I expected out of the rifle, I would fall back on 4831 or 4831SC. Wasn't until #9 or 10 of those rifles that I smartened up and started out with 4831. Guess that I'm a slow learner. I love to check out the possibilities of each rifle, but I've found that 4831 always gave me better than MOA (minute of animal) accuracy and it didn't matter if it was a woodchuck, coyote whitetail, muley or an elk, they all tipped over. Good luck on your voyage.

 

[Axlrod]

Thanks for the detailed and thoughtful reply.

I wouldn’t be reloading if I didn’t want to tinker with it, this gun shoots factory loaded partitions really well, but this gives me something to figure out.

My questions aren’t just for this gun or bullet, it’s more learning what sources to put a little more faith in. Everyone here turned to a page or asked a friend where to start with a given load, just too many options otherwise. Gordon’s is only as good as what people entered, and I’ve yet to find a manual that doesn’t milk a 24” barrel for all it’s worth.

I wouldn't pay much attention to what he says in general, but specifaclly here. Short cut powders benefit to reloaders is, they work way better in powder measures & funnels than long cut stick powders. He clearly has no experience with powder measures, funnels, or powder.
Also Hodgdon quit making the reg H4831 when they came out with short cut, so wrong again, there is no vast conspiracy to "market" more powder.

In the 270 I have had very good results with H4831sc. So if it doesn't shoot good, your gun might not like that bullet.

 

[TaperPin]

Thanks for the detailed and thoughtful reply.

I wouldn’t be reloading if I didn’t want to tinker with it, this gun shoots factory loaded partitions really well, but this gives me something to figure out.

My questions aren’t just for this gun or bullet, it’s more learning what sources to put a little more faith in. Everyone here turned to a page or asked a friend where to start with a given load, just too many options otherwise. Gordon’s is only as good as what people entered, and I’ve yet to find a manual that doesn’t milk a 24” barrel for all it’s worth.

Sounds like you’re having fun and Gordon’s is a great place to start if it’s double checked against other published sources just to make sure the load is in the ballpark. One of the nice things about reloading is everything is testable. It should be interesting to see how close Gordon’s is to what you see at the range, or what’s published in other sources. The FAQ page is worth reading through and does a good job of reminding the user of the variability in components so the user has to allow any numbers have some wiggle room.

The pressure curves shown for different loads are very educational to what’s going on in the bore.