Home Forums Reloading Big Game Rifles H380 Load for 243 Sierra GK 100gr & Nosler BT 90gr?

Where, troll, did I say "not good results"?

I hope to load up some this week and go shoot them over chronograph this weekend. If the chrono survives, I'm calling it a win. I'm thinking I'll pull the bolt, set rifle up on my lead sled, bubble level for elevation, insert a bore snake and tie some string on it to extend it out longer then put a string level on it to level it - giving me a point of reference for bullet path. I don't have a laser bore sight device. Any better methods that are dirt simple?

yeah bore sight

To bore sight ???

No...to make sure I set up my rifle to pass through the chronograph window without smashing it to bits.

👍😉😎

Get the rifle set up on the bags so the reticle is on target. Turn the scope down if it's a variable to maximize the field of view. You can check the alignment with the chrono that way to start. Walk down range and look back over the chrono at the rifle. You should be able to see the reticle looking back at the scope. if you can't then move your head around until you see the reticle centered up. When you're looking dead straight at the rifle pointed at you is that line of sight over and in line with the chrono? if not, then adjust the position of the chrono until it is. Remember you left the rifle aimed at your target, so move the chrono to suit.

Just remove the scope off the rifle.. it'll be easier.


H 380 with 90 grain bullets: https://stevespages.com/243_2_90.html. 33 to 44 grains.

H 380 with 100 grain bullets: https://stevespages.com/243_2_100.html 32 to 40.5 grains.

Contrary to what others have said on this thread, I have used plenty of H 380 in my 243s, along with a lot of other powders... BUT since you asked , here are two reference points above.

Since you are in Texas and it stays hot there, well into hunting season, the only thing I'll pass on, is don't use max load data, in Texas heat.. back off a couple of grains and it will be just fine... here in Oregon, temps are down low enough in October hunting season, H 380 is of no worries.

I've always found it to be accurate in any of the 243s I shoot, with bullets from 55 to 105 grains, with a one in 10 twist barrel. They are accurate to minute of sage rat, so being accurate enough to take down a deer, and especially at 200 yds and under should be a piece of cake.... even if someone is cross eyed, and a lousy shot.

I've found few powders that don't do a good job in a 243.. so few in fact I can't even think of one at the moment.

Use up your two pounds of H 380, and try something else if ya want to... but the H 380 ya got won't fail ya.

I couldn't count real quick all of the powders I use in the 243s over the decades. They all were more than minute of Whitetail and Blacktail. Stay away from max loads on hot days, but other than that, it serves ya well. I've always found H 380 is cheaper than many other powders, and also more available than all the popular powders at times like this.

If I had to pick a favorite or several favorites for the 243s, I tend to lean toward IMR 4064, IMR 4895 and RL 15. I don't use much 4350 in the 243, only because everyone else seems to want to...but I get the same results out of about any other rifle powder for a 243.

For kids, Lord knows how many times I've helped kids do handloads of Blue Dot, SR 4759, 4198, RL 7 for their first deer hunts when they are just starting out...hell even Unique. Even with those powders, the 243s have not failed to bring home the venison, out to 200 yds and further... They don't recoil much, so the kids can shoot them, both well and with confidence in them.

With 22 grains of Blue Dot, you can run a 90 grain bullet at 2700 fps MV, and a 100 grain bullet at 2600 fps MV., and the recoil is noticeably less than a 40 to 44 grain charge of 4350, yet is still more than enough of being up to the job at hand. Less recoil and kids and women can place their shot more accurately, not being afraid of the recoil.

There are a whole bunch of powder options for just the 243. pick one or use what ya got... any of them will get the job done... and its easier to place the bullet in the right spot,.

A lab radar or magnetospeed (my budget) solves a lot of chronograph problems, including the terribly inconsistent data obtained with an optical chrono.

Sorry. considering how close it is to you shooting I thought you meant sighting in your rifle too.

Thank you Seafire!! That's very helpful info - esp about the Texas heat and max loads.

One question on the load ranges shown. I did see H380 on the Hodgdon data center and the min max load ranges were 38-40.5 for 90 grain and 34.0 to 36.0 for 100 grain. Quite a bit lower than references above and probably has a big safety factor built into it coming from powder mfr.

It is safe to start at 1.0 grain below Hodgdon max load and work up to 2 grains below your reference max - watching for signs of pressure? So that would be 90 grain starting at 39.5 working up to 42.0 and 100 grain starting at 35.0 working up to 38.5.

I used that recipe as an all round varmint/deer load in my .243's for years.

4 pages in and no one suggests looking at a load manual or online data. Fu cking funny..

You know well enough that there’s too many options in a load manual to drive a newb to ask questions, l did we all did! 🤣

First round of reloads complete. Nosler 90 BT ranging from 36.1 to 39.4 in 10 steps increasing load 1% per step. Seated all 0.023" off jam 2.390" length base to ogive (using Hornady comparator). Went with the H380 I had. Hope to start testing this weekend.

oh I don't know...

That guy over in Grants Pass, OR posted some reference load data using H 380 and a whole list of other powders for the 243.

but you and I have both been around long enough to know, let the rifle tell you what it likes, vs load data from any manual.. manuals are a reference, NOT a bible. Dont assume two barrels are going to like the same charges.

I've used plenty of H 380 over the years in a number of calibers.. when I'm told it won't work... so I try it out. and have always found it did just fine... If it can give me minute of sage rat, it'll easily give me minute of whitetail or blacktail.. and my standards for that is 200 to 250 yds..

from a guy who has been around a long time in the business world.... if a powder doesn't work well, then it quits selling off the shelves... if it quits selling, then it is discontinued... H 380 has been around a long time on the shelves each year... that's the real proof if its going to work or not.

Whenever I start reloading for a new rifle I always try at least 4 or 5 different powders. Usually at least one or two will work. There are times when one particular powder comes highly recommended and more often than not, gives good results on the first try. H4350 and the 6.5 Creedmoor immediately comes to mind.

The internet has opened up a lot of information, and I use it as often as needed. One can find reloading information for anything you want to look up. Some of it is probably best taken with a grain of salt, but there is also some good stuff out there.

IMR 4350 is the easy button. Retumbo in my 105gr loads but it measures like scheit.

Ruger M77 MK II UL, 20" barrel.

FC case 175.5gr, 43.5gr H-4831sc, CCI 200, 95gr NBT. .025 off ogive, 2825fps from 20" barrel, accurate, < 1" with my 16 year old grandson.

MPBR 277 yards.

Interesting results. Hodgdon manual for 90grain bullet is 38.0 to 40.5. I started at 36.1 and went up in steps of 1% more powder (0.3 to 0.4 grains). Bullet is Nosler 90 BT seated at 0.023" off jam - length base to ogive of 2.390" using Hornady comparator

#1 H380 36.1 2894 fps
#2 " " 36.4 2905
#3 " " 36.8 2929
#4 " " 37.2 2964


#4 reached clear signs of pressure - flattened primer and bolt was sticky to open. I quit at that point. 37.2 is way below Hodgdon upper limit of 40.0. Is that because I am running my bullet seated longer than their factory standard?

I suppose I will load up a few more at steps going down from 36.1 to see what the results are and will call 36.8 max. I don't see much need to load it that hot though since 1,2 and 3 were all within 35 fps.

Thoughts?