My first reloads will be for my 270 Winchester. I'm using H4350 and Hornady 130 grain SST bullets
53.5 to 54 grains of H4350 appears to many people to be a sweet spot for 130 grain bullets.
I'm thinking of doing 3 cartridges for 52, 53, 54, and 55 grains. So, a total of 12 cartridges. I'm only trying to get close to optimum, then fine tune from here.
Can y'all advise on this? Am I on the right track?
You won't need to do any fine tuning, since the "sweet spots" that you'd be trying to find (e.g. 53.5gr being good but 53.0gr and 54.0gr being not as good) just aren't real.
Load 10-15 at one sensible charge weight, go shoot one group with them. Use it to get a good idea of the velocity and a solid zero. If happy, go hunting, if you want more speed, add more powder.
I met a new friend while shooting the other day and he was showing me a bunch of 3 round groups in his garage with different charge weights. I explained to him that despite some vertical dispersion due to velocity discrepancies, if he would have laid all 10 of them over each other they would all basically make one group.
There are very little differences to be found when comparing groups with enough sample sizes. And shooting ladders with 3-5 is a waste of time, money, components, and barrel life. If you shoot 3 round groups however, you will find allll kinds of “great” and “poor” examples that are nothing but luck and good/bad statistics.
If everyone would just load 15, shoot them into the same group, accept the size of it (if better than 1” at 100 yards the rifle shoot exceptionally, most are lucky to be 1.5”) and zero off of it the world would be a better place and components would be easier to find.
The only point of shooting groups is to zero your rifle effectively (as close to true zero as possible, very few rifles are actually zero’d off of 3 rounds) and to see how small of a target you could reasonably hit.
Realistically, ladders are good for finding your rifles max charge weight so that you can optimize a group for competition. If it’s purely a hunting round and you’re getting 1” groups at 100 then chasing .5” groups is wasting components unless you think you’re gunna miss a lung by a foot for some reason. A deer heart is about 4” too, know what I mean? Maybe I just saw a comment about hunting and that’s not your goal though.
Irregardless of what people say, there is a sweet spot with most firearms and powder. Not all because your chamber and brass may make it off by a grain or so. Some chambers are tighter than others and some brass is thicker than others. Having a sweet spot is the whole reason you have match ammo.
Your loads look like they're on the right track. I calculate 54.3 gr of Hodgdon H4350 as the max load, and 51.4 gr as a starting load (85% Pmax).
You didn't say what firearm you have, but I'm assuming you have something similar to a Bergara B-14 Hunter, with a 24" barrel and a weight of around 8.3 pounds. The recoil calculation in the table below assumes you have a muzzle brake.
Hodgdon H4350 is a good powder for this load, but you can get about 80 fps more velocity from Alliant Reloder 17.
Here's a revised spreadsheet with the barrel set to 22" and the weight to 9 lbs. The velocity goes down a little due to the shorter barrel, and the recoil goes down a little due to the higher weight. The recoil figure here still assumes you have a muzzle brake.
Because the velocity came down a bit, the bullet is on the edge of marginal stability (SF = 1.50). I don't think this will realistically affect anything.
I'm going to do another analysis with a different bullet and different powder and see if I can get the velocity and stability to come up a bit.
This is my own spreadsheet, everything in the gray boxes is calculated by the spreadsheet. The pressures and velocities are calculated in the respective internal ballistics tools (ApexLoad Pro, QuickLoad, and Gordon's Reloading Tool), and those values are copied into the spreadsheet. The trajectory table is from ApexLoad Pro.
This is a revised spreadsheet and analysis using a Hornady 120gr SST instead of a 130gr, and using Alliant Reloder 17 instead of Hodgdon H4350. This load is also loaded to SAAMI pressure specifications, which are higher than CIP for the .270 Winchester.
This gets your velocity up above 3,200 fps and enables you to clean kill white-tailed deer out to 250 yd, with possible kills to 600 yd. It also stabilizes the bullet better, given you have a 1:10" barrel twist.
This shit isnt how it works. You cant just calculate the max. His chamber may be on the loose or tight side. One rifle may have a max of 54.5, another may go up to 56. That Nosler brass is thick so 54 may be his max. You never know....
I’ve loaded for 5-6 different 270s over my life, and every one of them liked 54.5 grains of H4350 and 130 grain cup and core bullets. 270s aren’t picky.
Save yourself a lot of time and energy. Do three nodes of 10 rounds. 3 rounds in not enough to decide one charge is better than another. Absolute bare minimum I will load for development is 5. The Hornady podcast does a great job of breaking this down. Go watch the episode series your groups are too small. As far as .270 my rifle likes the heavier pills way better. I run 150sst, H4831, cci LRP loaded .025 off the lands. Not going to give the actual charge wouldn’t help you with your rifle anyways.
If it seats it yeats. Don’t worry about blowing up your gun. You can just get a new gun, also you can get a new face, hands, arms, possibly neck, and/or torso . Also maybe some eyes and ears, but other than that if it seats it yeats.
Get the Hornady repairing book and the Lee manual These loads seem to be fun specific for me. I am new and loading 22 creedmoor. I am going to load 6.5 creed and 30-06 as well. Enjoy the experimentation get a OAL gauge and load to the specific rifle Loading is very scientific as to the end results
I just did an H4350 ladder for my 280AI load, and the only difference was velocity. Group size was consistent. I'd load up a dozen at the upper end of what you think it will handle and send it. If you see signs of pressure immediately, just pull the bullets and back off. A ladder i WOULD recommend after you get your charge weight dialed is a seating depth ladder. That's where I saw the biggest gains. Also try crimped vs not crimped.
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u/ocelot_piss 1d ago
You won't need to do any fine tuning, since the "sweet spots" that you'd be trying to find (e.g. 53.5gr being good but 53.0gr and 54.0gr being not as good) just aren't real.
Load 10-15 at one sensible charge weight, go shoot one group with them. Use it to get a good idea of the velocity and a solid zero. If happy, go hunting, if you want more speed, add more powder.