Thread: safe to compress powder during reload?

I've loaded this 303 case with 46.5 grains of AR2209.
Is this normal here? See photo attached.
The powder takes almost up to halfway in the neck.
46.9 grains is supposed to be the maximum load for this cartridge and projectile, so im getting close.
Am using 174 grain projectiles.
I have compared my load on 2 sets of scales and the second scale reads even less, but they are so damn sensitive that a single granule of powder is enough to change the reading, making it impossible to get both zeroed the same.
I read that some heavier brass can't always fit a load, this is HXP.

Perfectly normal.and somewhat desirable.

A full case is consistant between loads,all will have it the same. I just pulled some 270 loads and reduced powder charge by 1.5 grains and they are still full to the neck. If you tap side of case the powder will settle somewhat.

Can you tap the case a bit to settle the powder a bit deeper ?
Personally I don't mind a slight powder compress but avoid going as far as heavy compression.
I have a small piece of leather on my bench. If I want to tap down a charge a bit I turn the case slightly so the primer isn't contacted and tap away on the leather until I'm happy. Put a finger over the case mouth to stop kernels jumping out

Compressing powder isn't inherently unsafe. If it was, manufacturers wouldn't publish data for you to follow with the "C" denoting that the charge is expected to be compressed.

There are certain powders such as Trail Boss where they say do not under any circumstances compress it, because it can break the kernels, changing their surface area, dangerously affecting burn rate. AR2209 is not one of them though.

That said, if you reach compression significantly earlier than expected, and end up compressing powder much more than you should have to... then maybe? The chrono is still your best guide here. If you work up the load from a non-compressed start point and are getting the speeds that you expect along the way as you start to crunch the powder down, then the pressure will be roughly in line too. Another good reason to work up - reassurance - rather than trying to nail it right off the bat.

I tend to avoid compressed loads mainly because the added seating force can cause the stem to deform the bullet jacket and leave a ring around it. And it messes with COL too.

Yes I noticed the "C" on some manuals.
I dont think I've got anything to worry, just new to this and playing it safe.
Comparing other reloading manuals, I see the maximum load for this charge is rated at 48 grains, so I should be safe.

If you are unsure of scales....keep a couple of lighter projectiles on hand.a fifty grain 223 projectiles will do nicely.

Why are you loading up so close to book maximum if your just starting to reload??? You have asked questions and been told by many,the 303 Brit is hard on brass,keep loads mild.

You're fine. I load 48.0 grains of 2209 in my .303 with a 180 grain bullet (for 2415fps). And I wouldn't even consider that a max load in my rifle.

In general compressing powder is no issue. I have loaded cases just using the cartridge as a scoop and loading it right full up to the case mouth, and seating a bullet top on that.

You can compress it as much as you like right up until:
By doing so the pressure you use distorts the case itself, or until you have so much powder compression that neck tension will not hold the bullet in place.
(In the last case, you load your cartridges, measure their OAL, and then leave them overnight. Measure them again in the morning and if they are longer than they were before, the powder is pushing the bullet out.)

Avoid heavy compression if you're using micrometer seating dies as the inner components are finer and more sensitive. Standard seating dies are much tougher and will probably keep seating until there is no more give against the powder.

Greetings,
46.5 grains of AR2209 with the 174 grain is pretty much max with the current faster lots of AR2209 and I doubt if you will get away with neck sizing at that level. The Hodgdons data is quite old and ADI listed 47 grains max in 2000 which is definitely the slower powder. I would likely start at 42 grains, chronograph and look for the primers backed out of the case. This shows you are not stretching the cases.
GPM

My ADI 2016 manual lists
174gbullet
2209
43gr start
48gr Compressed as max. 41,900 CUP

Originally Posted by grandpamac

Greetings,
46.5 grains of AR2209 with the 174 grain is pretty much max with the current faster lots of AR2209 and I doubt if you will get away with neck sizing at that level. The Hodgdons data is quite old and ADI listed 47 grains max in 2000 which is definitely the slower powder. I would likely start at 42 grains, chronograph and look for the primers backed out of the case. This shows you are not stretching the cases.
GPM

Hear this from you a lot. I don't think it's particularly helpful. The 2209 data is still fine to follow otherwise you'd think ADI would have removed or revised it. Same goes for 8208 too.

Just work up and watch the velocity OP. Reloading 101.

Just gently tap the case up and down a few times to get the powder to settle. An intriguing calibre to reload.

Originally Posted by TeRei

Just gently tap the case up and down a few times to get the powder to settle. An intriguing calibre to reload.

Lol. I used a battery electric tooth brush.