Max Load data for 183 Sierras, .284 winchester

[RNation]

I'm loading some 183 HPBT Sierras for a 284 winchester. Following an older post I found in here I loaded in increments between 51.5gr (2770 fps) of H4350 and 52.3gr (2823 fps) of H 4350 out of a 8.5 twist barrel.

Now I'm not an expert and this is actually my first time fine tuning a load although I've been reloading for a few years. But based on what I could see there was no high pressure signs, should I keep raising the increments until I see some high pressure signs or is that not necessarily going to create the best bullet for my gun? I suppose the sweet spot for an individual gun is not always found with more velocity?

I did call Sierra yesterday and they told me there is currently no data for this round, even though it is a few years old.

Thanks in advance fellas.

 

[Cowtownup]

I ran my ladder test with the 180 Hybrid up to 53.1 grains of H4350. I never used anything but H4831sc on the 183 SMKs. Some specifics on what barrel length, freebore, etc. may help us help you better... FWIW I believe that most folks are running the 180's between 51-52 grains of H4350.

 

[RNation]

The length is 28" Criterion match barrel with a 8.5 twist and the barrel bore is .220.

I use the H4350 because I also use it with 3 of my other calibers. If H4831sc will make a huge difference then I'm up for changing, but if it works close to the same I'll just stick with the H4350.

Also, when I test these I have bi-pod in the front and a sand bag in the back. But I have to apply a little pressure on the bag in order to get the crosshairs on point. I'm not sure iof this is an ideal scenario because it allow for some human error. Am I going about that wrong?

 

[Cowtownup]

A friend of mine has this same barrel and he has just started load development with H4350 and 180 Hybrids. I'll ask him what he has found out...

 

[Willow]

I'm loading some 183 HPBT Sierras for a 284 winchester. Following an older post I found in here I loaded in increments between 51.5gr (2770 fps) of H4350 and 52.3gr (2823 fps) of H 4350 out of a 8.5 twist barrel.

Now I'm not an expert and this is actually my first time fine tuning a load although I've been reloading for a few years. But based on what I could see there was no high pressure signs, should I keep raising the increments until I see some high pressure signs or is that not necessarily going to create the best bullet for my gun? I suppose the sweet spot for an individual gun is not always found with more velocity?

I did call Sierra yesterday and they told me there is currently no data for this round, even though it is a few years old.

Thanks in advance fellas.

The big problem with the 284 is that it doesn't handle pressure well and the primer pockets like to open up. I think for the load you have, going too much higher, you're going to see primer pockets going, based on previous experience with it. Don't worry about the velocity so much, it may be your gun shoots lights out at a lower node, either way, you're using a high BC bullet so follow the accuracy rather than velocity.

 

[FeMan]

I had one barrel that loved 180 Hybrids over 51.6 grains of H4350 and F210 primers. The first time I shot it over a Lab Radar I thought the chrono was broken; 2804, 2804, 2804. It shot lights-out accurate too. I started getting pressure around 52. All my other barrels have preferred H4831 and BR2's. My current load is 183 smks at 2770 jumped 50-thousandths. If I try and push them faster than that they just don't group. With the 284 and its rebated rim you should be able to feel pressure at bolt lift pretty readily.

A comment on rear bag and bipod. If you are pushing down on the rear bag to align the crosshairs, you are risking vertical. If you are very careful and consistent you may be ok. I prefer to load the bipod, align everything and then bring the rear bag to the stock. It is a lot quicker and more consistent for me. I get a great waterline that way; no vertical flyers.

 

[RNation]

Thanks guys, that was some pretty solid info.

So far 52.3 seems to be my best group but I haven't went any higher than that. I'm going to go try out the oal tests today. Mine appears to be at the lands at 2.465 ish, so I will test from 2.464 down to 2.449 and see what I get.

 

[FeMan]

FWIW, the 183s have grouped best jumped 50 thousandths in my Rifle. They didn’t do well up close. Your results may be different of course.

 

[RNation]

Mine seemed to be best around .012 away.

 

[rebel107]

I can share a load using H4831sc. Look for around 2840fps, 54gns of powder and between 3-9 thou off, Lapua brass and BR2's & Benchmark barrel.

 

[RNation]

Do you think H4831sc will make for better groups than H4350? I'm willing to change the powder up if it'll be worth it. Right now I use H4350 for 1 or 2 other calibers so it's kind of my "go-to".

 

[Willow]

Do you think H4831sc will make for better groups than H4350? I'm willing to change the powder up if it'll be worth it. Right now I use H4350 for 1 or 2 other calibers so it's kind of my "go-to".

So H4350 and H4831sc are made by ADI powders in Australia. Here they are sold as ADI2209 and ADI2213SC respectively. Based on my experience, and seeing plenty of other guys more experienced than myself run 284s here, 2209/H4350 is the powder to run. You might be able to squeeze more speed out of 2213SC/4831sc, but 2209/4350 is where the accuracy is at. You have the powder on hand - stick with it. I've tried 2213SC in 284 and 280AI configuration and 2209 was better in both guns, less vertical and tighter groups. 2209/4350 works exceptionally well in the 7SAUM also, Rod Davies shot his way to victory in F-Open at the WC in Canada last year using H4350. Depending on what calibre you're running, it might chew the barrel up slightly faster, but it's reputation for accuracy cannot be understated.