243 Ackley and H4350?

[Greg Duerr]

I have a .243 AI and 10 lbs of H4350 and not much of any other kind of powder. Im new at this so Im starting off with 44.0 gr of H4350 and working up by .5gr..........................I realize that your rifle will tell you when enough is enough but for those of you who do use this combination when did your rifle tell you enough, and what was that ..................Im shooting 100gr Sierra Pro Hunter's 24in barrel...............

What would be a good starting load....................the Sierra bullet teck told me to start out at 37gr.

For those of you who have a lot more experiance than I do .............??

 

[westcliffe01]

If using Hodgdon powder, first place to visit is the manufacturers website:
Cartridge Loads - Hodgdon Reloading Data Center - data.hodgdon.com

For the regular 243 with a 100gr bullet the load listed is from 37-40gr. With an AI the usual rule is that it may take up to 10% more powder, particularly if the bullet is seated long.

Another good source is .243 Win + .243 AI Cartridge Guide

They list ackley loads, but beware that many of the loads listed are very hot and with long seated bullets.

4350 is a good powder for the 243 and 243AI You will see that the loads on 6mmbr do not get to the 243AI+10% level, but are rather just a grain or 2 more.

I was unable to get a decent amount of 4350 which is why I am using H100V (which is relatively easy to get) and I will just have to see how consistent it is over different temperatures. I have a bunch of superformance powder which I bought by mistake and I will be trying that also. These are all relatively slow powders.

I would never start with a Min load. Rather start in the middle or even directly at 39gr. When I worked up my fireforming load, I started directly with 41gr of H100V which is the max load in the parent cartridge. Because of the expansion of the brass the pressure peaks out lower than in a regular chamber and this load has shot 1/2 moa for me.

 

[TOM H]

I have a .243 AI and 10 lbs of H4350 and not much of any other kind of powder. Im new at this so Im starting off with 44.0 gr of H4350 and working up by .5gr..........................I realize that your rifle will tell you when enough is enough but for those of you who do use this combination when did your rifle tell you enough, and what was that ..................Im shooting 100gr Sierra Pro Hunter's 24in barrel...............

What would be a good starting load....................the Sierra bullet teck told me to start out at 37gr.

For those of you who have a lot more experiance than I do .............??

You posted this last month.

http://www.longrangehunting.com/forums/f28/h4350-flat-base-bullets-now-success-114054/

 

[Greg Duerr]

Im refering to what the max load might be as I'm not sure. I got great accuracy with 44.0 but will we trying 44.5, 45.0, 45.5, and 46.0.............The max load varies from reloading book to reloading book for the basic .243. Some show 40.0 soome 42.0....................

 

[Cascade_Sherpa]

It sounds like you got some pretty solid info from the posts above but I'll chime in on what little I've been told from my gunsmith on my .243AI. The most common recipes he gave me was this:

105 gr Amax, 47.5 grains of RL22
Hornady 70 gr spire points, 47 grains of H414 at 2.615 OAL
85 grain TSX, 46 grains of Ramshot Hunter, CCi 200 primer

Also he recommended H1000 and RL22 powders but no specific load data.

What are the specs on the .243 AI you are shooting? barrel length and twist?

John

 

[65WSM]

Which Hodgdon 4350 do you have. My recent experience with 6mm Remington says that your burn rate is about right for 100 gr bullets. You will get more velocity from a modern double base powder. I have found SuperPerformance fast with 95gr Ballistic Tips and 90 bergers in my 10 twist barrel. VV N560 will also give you more velocity. IMR 100V is fast with lighter bullets 87 and 90 gr.

The original Hodgdon 4350 was surplus, intended for 50 cal military ammo. Weatherby launched his company loading surplus 4350 in his bottle sehaped cartridges like .257, 270, 7mm Weatherby. This was part of the original IMR series manufactured in Delaware by DuPont.

The second source was CIL in Canada. IMR announced that they would build a new facility to make powder in Virginia but I have never seen any product from USA that was not made by DuPont.

My most recent IMR powders have been made by the French owned ADI in Australia.

A lot of data for H-4350 is old and does not match the currently available components. I suspect the formula has also been updated. I get more zoom out of the same charge of ADI IMR 4831 than I did with CIL H-4831.

Because of conflicting origins the Tech at Sierra may have been cautious with H-4350. I would be.
.

 

[clem81]

i have been working with my 243ai and thought i had a great load. 45.5 gr h414 sierra gameking 85. getting .5-.75 groups. tried some h4831 with 95 gr SMK and holy cow .300 dia groups, and it holds together at 200 and 300. the h4831 has been a godsend for me. really shoots 80 gr noslers well also. i need to check speed but for a .760 dia barrel 26 in long im pretty happy

 

[Greg Duerr]

My big problem with my rifle is the throut .................its way to long and wide and will NOT shoot boat-tail bullets. I addressed this problem to the Smith that built the Rifle and he has never written back. I considering having it rebarreled to the 6XC after hunting season. Having only flat base bullets to shoot as that is all that will shoot out of it, is a real downer...........not to many out there. When shooting boat-tails It shoots into about 1.00 to 1.25 with flat base its around .5 to .4 with some going into the high .3's.................and thats with H4350. There are a lot of bullets I would like to try but all are boat-tails.......................I dont like being hadicaped ............and after spending $2000 on the gun I want more options...................Right now I will be shooting 100gr Sierra Pro Hunters as they shoot great in this gun and will try the berger 80gr Flat base bullets as well........................We will see what kind of groups I get monday with 44.5gr of H4350 up to 46.0.....................Speed kills as they say so lets see what happens. The Lapua brass I have has really held up to the stiff loads I have tried ...