Can u explain the finer points of picking a powder to me?

kykamo

kykamo

Regular
Rating - 100%
20   0   0
Location
St Paul, AB
Hey,

I'm new to reloading. I just started loading my 270 win and want to start for my dad's 7mm rem mag and I just bought a pistol carbine I want to load for.

When I went to pick my components for my 270, I started with the bullet then went to pick a powder suitable for the bullet weight. The only thing I knew about picking powder was to find published data that has the general speed I want with the lowest amount of powder used to get it for recoil purposes. Thought I was doing alright. I picked this http://www.hodgdonreloading.com/data/rifle?&CartridgeName=270+Winchester&OrderBW%5B%5D=140&Manufacturer%5B%5D=IMR&Powder%5B%5D=IMR+4166 I'm happy with my choice.

But trying to find a low powder grain load for the 7mm rem mag isn't working for me and I don't know why. The imr 4166 powder hasn't been published for 7mm rem mag and I'm curious how it would perform in a 7mm. How come every powder option isn't published in reload manuals?

My reloading journey has continued when. I tried to find a good load for my pistol carbine. I first figured that any pistol load would be fine in my carbine and can just expect to add 200 fps to the performance. Or I could find a slower burning powder which might perform even better out of my carbine. Hard to know tho because all the published data is for 4" pistols. So then I read this article on relative burn rate, http://www.chuckhawks.com/powder_relative_burn_rate.htm
It blew my mind! But I don't understand what it's talking about exactly. And now I'm worried some pistol loads could create a higher dangerous pressure in my carbine?

Can u explain to me how to figure this stuff out so I can best reload my stuff?

Thanks guys, sorry for the long winded post. I just need some clarification
 
Generally the faster powders are pistol and shotgun powders. The medium speed are standard rifle rounds , the slowest powders for large case or magnum caliber. Case capacity will be deciding for which speed of powder generally.

Get reloading books, most of them will give you a short write up on cartridge, what powders work well, best accuracy load that they had. Lyman manual is good, they use a variety of bullet manufacturers in their data. Check Internet as well. DO NOT USE DATA UNLESS YOU CAN VERIFY WITH PUBLISHED DATA. You can find both good and bad info on the Internet.

Some powders will work well in multiple applications, Varget, IMR 4895, are two that I use for a variety of calibers. These are medium speed powders. I don't have any magnum calibers I load for so these can cover most of the 10 or so calibers I load for. If I had magnum rifles I probably would need a better choice for best performance.

Use pistol data, it will be fine. Can do load development as normal. Pistol rounds are hard to read for excessive pressure so stay within published data. I have a pcc as well and use normal data. If I need more performance then I go to rifle rounds.
 
Your going about it the right way. A big mistake I used to make was to have one, do it all, powder for everything. It's just easier to have a preferred powder for each cartridge you reload. I pick a bullet, then consult multiple manuals to see what gives the highest velocity because that usually means it will be the most efficient burn rate for that application. Don't be cheap and try to get away with light charges. Remember that the case is most efficient and probably most accurate when it's close to capacity. For 7mm I like h4831 and imr7828.
 
There are a number of variables that have an effect on powder selection, but by referencing published data it simplifies it to a great degree. Each chambering will have a range of burn rates (and powders in that range as a result) that are suited to it based upon the case capacity, bore size and bullet weight.

In your case, you are looking at two chamberings with similar bores and reasonably similar bullet weights, but a significant difference in case capacity. While there are powders that overlap and perform well in both, generally the 7mm RM will perform with slower burning powders, while the .270 works better with powders that are a couple steps faster in burn rate than the 7mm prefers.

In order to make one powder work for both, it will need to be in the slower end of the range for a .270 (ie 4831), which is mid-slow in the range for a 7mm RM. By choosing faster powders in the .270's favored burn rates, they end up faster than normally suited for the 7mm.

My process for selecting a powder for a given rifle chambering is to select based upon powders that give velocity numbers that are close to the maximum the cartridge is capable of at safe pressures. I then develop loads for acceptable velocity and accuracy from that point and let the results determine if the powder I tried is giving the result I want. Usually for rifle loads,this works to give an accurate load at reasonable velocity, that uses the potential of a given chambering. If I am looking for a different result, such as a mild pistol load, I will select a powder that gives the desired velocity at reasonable pressures, to again suit the load to the intended use.

In your case, you are selecting based upon minimum powder charge, trying to limit the recoil or powder cost in the load, which means a faster powder is selected to achieve a given pressure/velocity, as faster burn rates mean the powder burns quicker and thus builds pressure quicker, so less powder is required to stay under the pressure limits for a given chambering. In doing so, you may be leaving velocity or accuracy on the table, based upon your objectives, when compared to what the capabilities of the chambering are.

Ultimately it is up to you as to what you want the load to achieve, and selecting based upon powders likely to give your result. Certain powders are favorites within a given chambering, as they often give a load that meets the desired results, which is normally the potential velocity, combined with acceptable accuracy that the chambering can deliver when we are talking rifle loads.

I would suggest picking powders that best suit the round you are loading, rather than seeking a compromise that works ok in both, but optimum in neither chambering.
 
kykamo said:
Hey,

I'm new to reloading. I just started loading my 270 win and want to start for my dad's 7mm rem mag and I just bought a pistol carbine I want to load for.

When I went to pick my components for my 270, I started with the bullet then went to pick a powder suitable for the bullet weight. The only thing I knew about picking powder was to find published data that has the general speed I want with the lowest amount of powder used to get it for recoil purposes. Thought I was doing alright. I picked this http://www.hodgdonreloading.com/dat...BW[]=140&Manufacturer[]=IMR&Powder[]=IMR+4166 I'm happy with my choice.

But trying to find a low powder grain load for the 7mm rem mag isn't working for me and I don't know why. The imr 4166 powder hasn't been published for 7mm rem mag and I'm curious how it would perform in a 7mm. How come every powder option isn't published in reload manuals?

My reloading journey has continued when. I tried to find a good load for my pistol carbine. I first figured that any pistol load would be fine in my carbine and can just expect to add 200 fps to the performance. Or I could find a slower burning powder which might perform even better out of my carbine. Hard to know tho because all the published data is for 4" pistols. So then I read this article on relative burn rate, http://www.chuckhawks.com/powder_relative_burn_rate.htm
It blew my mind! But I don't understand what it's talking about exactly. And now I'm worried some pistol loads could create a higher dangerous pressure in my carbine?

Can u explain to me how to figure this stuff out so I can best reload my stuff?

Thanks guys, sorry for the long winded post. I just need some clarification
Click to expand...

The best way to figure it out is to look at reloading manuals.

The basic concept of why a powder is suitable or better for a given cartridge is based on burn speed and case volume. Some powders are better suited to some cartridges and that's why you won't see reloading manuals listing every possible powder with every cartridge. They pick the powders that will likely work best in that cartridge for that bullet weight. IF IMR4166 isn't listed in the 7mmRM data, then it's probably not a great powder for use in 7mmRM. It is probably too fast, and larger capacity cases generally work better with slower burning powders.

Pistol cartridges are usually smaller powder capacity and lower pressure than rifle cartridges, which generally means that faster powders are better suited to work in pistol cartridges - again it's about the powder burn rate and case volume that is suitable for that cartridge.

There is not a bunch that you have to figure out - the reloading manuals have already determined what a suitable powders are and that's why we use reloading manuals. Look at the pressure and velocity data, check more than one source, read or ask in the forum if you are still unsure about what powder and then have at it.
 
Don't be worried about charge weight. Be worried about preformance (accuracy mainly. Speed is important to some too) if you get really good preformance from what you chose than great. If not, go get some h4350 or something else to try.

I haven't heard charge weight being related to recoil when comparing different powders...? Obviously more of the same powder will recoil more, but i don't think that is a universal standard between powders.
 
Suther said:
Don't be worried about charge weight. Be worried about preformance (accuracy mainly. Speed is important to some too) if you get really good preformance from what you chose than great. If not, go get some h4350 or something else to try.

I haven't heard charge weight being related to recoil when comparing different powders...? Obviously more of the same powder will recoil more, but i don't think that is a universal standard between powders.
Click to expand...

In recoil calculators they always ask about grains of powder for the load. It's bullet weight, speed and grains of powder so I guess I matters? I does seem magical to me that u can achieve the same velocity with less powder. But I guess it has to do with pressure

Thanks for the info guys. I didn't realize the great case capacity difference between 270 and 7rem mag. I need to do more research on the 7mm.

I'm still curious about how to develop a load for my PCC. How does pressure behave in a pistol vs my carbine?
 
kykamo said:
In recoil calculators they always ask about grains of powder for the load. It's bullet weight, speed and grains of powder so I guess I matters? I does seem magical to me that u can achieve the same velocity with less powder. But I guess it has to do with pressure

Thanks for the info guys. I didn't realize the great case capacity difference between 270 and 7rem mag. I need to do more research on the 7mm.

I'm still curious about how to develop a load for my PCC. How does pressure behave in a pistol vs my carbine?
Click to expand...

I can't say I've ever really played with a recoil calculator... Do they ask the type of powder? Or do they just ask for the number of grains? Also, I wouldn't be too concerned about that. Recoil is such a subjective thing, trying to calculate it is practically pointless.

As for your carbine, just use normal loads. Your carbine is basically a handgun with a 19" (or whatever length) barrel. The case still has the same capacity, and the gun was still designed around reliably running factory ammo, not some special carbine load. At least, thats what I would do.
 
A great question and you may find one powder suitable for the two rifles if one wants to bend a bit as to bullet weight.
With a 130 grain bullet in the 270 Re22 is the most accurate and the best hunting load.
In the 7mm RM, Re22 is in the picture with a 150 grain bullet and the 175.grain. That is not to say the 160 grain would not work but Re22 was not a favored load according to the Sierra Manual.
You will need a separate class of powder for handgun.
Nosler also lists "Most accurate Powder" and a most accurate load with other powders. The only time they showed Re22 was with the 175 grain in the 7mm RM but it was their accuracy choice.
These are starting points and you don't need to necessarily use their bullets.
 
Last edited:
I've had very good results with H4831 powder in the 243, 257 Roberts, 25-06, 264 Win Mag and 7mm Rem Mag., among others.
Not necessarily the "top of the chart" velocity loads, but good accuracy and useful for a wide range of bullet weights in each respective caliber.
 
Recoil is a function of weight of bullet, other factors the same (velocity). But the weight being blown out the muzzle is the bullet + the weight of the powder. So a calculator asks. But difference in powder charge, fast to slow powder is only about 10 gr. Almost nothing to consider.

Many powders will go bang, but a few of them are "real good". Since you have the ability to choose, choose a good powder - not based on a minor issue like economy of the powder charge.

I load 270 with RL22. I would be happy with 4831 or H450.

For 7mmRM I also use RL22, or RL25.

These powders tend to work in most rifles and give good accuracy with lots of power.

I have never heard of 4166 and it is not in my books. But I am an old fart.

Edit: I just Googled IMR 4166. It is a medium speed powder for 308Win. Much too fast to be a good 270 and 7Rem powder.

If you are looking at the new IMR powders, 4955 would be the one to buy. It is a slow powder.
 
Last edited:
I kinda went in the other direction. First, I looked at the tables online and in the books I have, then I purchased bullets for which I found exact or very close matches in those load tables, then I purchased a powder for which I found data in those tables.

As all my firearms are long-barreled, I usually go for the slowest powder I can find to minimize peak chamber pressure while maximizing muzzle velocity. I also prefer double base ball powder because they tend to meter well in my Hornady LnL press (which measures by volume). That's how I ended up with CFE Pistol for 9mm and H110 for .357mag.
 
Grawfr said:
I kinda went in the other direction. First, I looked at the tables online and in the books I have, then I purchased bullets for which I found exact or very close matches in those load tables, then I purchased a powder for which I found data in those tables.

As all my firearms are long-barreled, I usually go for the slowest powder I can find to minimize peak chamber pressure while maximizing muzzle velocity. I also prefer double base ball powder because they tend to meter well in my Hornady LnL press (which measures by volume). That's how I ended up with CFE Pistol for 9mm and H110 for .357mag.
Click to expand...

I also like to use ball powders because they meter so well. Nothing more frustrating and maybe dangerous that a powder that hangs up in the thrower.

But when you mention maximising velocities, you are also maximising pressures. the two go together. Nothing wrong with running high pressures, so long as it is not too high.

One thing to consider with slow powders is that some require high pressure to be reliable and accurate. H110 / 296 is an example. perfect for max velocity loads in 357 and 44 Mag, but not so good if you want to back off a bit for a medium power load.

I have a jug of 296 and use it for max velocity 357 loads. But for most of my 357 loads, I load quite warm, but not max, and for that I prefer 2400 or Universal. Both meter well, too, and are a bit more flexible that H110.
 
kykamo said:
In recoil calculators they always ask about grains of powder for the load. It's bullet weight, speed and grains of powder so I guess I matters? I does seem magical to me that u can achieve the same velocity with less powder. But I guess it has to do with pressure

Thanks for the info guys. I didn't realize the great case capacity difference between 270 and 7rem mag. I need to do more research on the 7mm.

I'm still curious about how to develop a load for my PCC. How does pressure behave in a pistol vs my carbine?
Click to expand...
A faster powder (less volume/weight of powder) has a sharper recoil impulse. A slower powder (more volume/weight of powder) has a more subdued recoil impulse.
If you are using a longer barrel you can use a slower powder. A short barrel with a slow powder may result in an incomplete burn.

By using a faster powder you may be getting a higher pressure spike which may be loosening your primer pockets requiring new brass quicker.
 
Yes, they were not thinking of us old guys when they started making those powders with strange numbers for names.
Back in the day when Jack O'Connor published good loads for us nearly every month in Outdoor Life, he said that 60 grains of the war surplus powder known as "4350 Data Powder," was an ideal load in a 270 with a 130 grain bullet and handloaders, probably numbered by the million, rushed out and loaded it up in their 270s. It was called 4350 data powder because you could safely use IMR 4350 data for loading the surplus powder. When Hodgdon's tagged the old surplus powder with their name and the number H4831, the load of 60 grains with a 130 grain bullet in a 270 was so widely used, that Hodgdon's just put those figures in their data list on the powder and never even tested it!
I still have a pound or so of the original war surplus (H4831) that came in 50 pound kegs and I have fairly recently tried it in three rifles in three different calibres and in all cases the velocity was about 100 fps more than the equivalent of the new canister H4831.
Back in the day we also soon learned that H4831 could be equally exchanged with Norma 205 and IMR 4350 could be exchanged in equal amounts with Norma 204.
Dang it, why did they have to start making powder with fancy names that we have never heard of!
 
You must log in or register to reply here.
Back
Top Bottom