Help me find pressure signs

satchamo

WKR
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Jan 23, 2014
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Indiana
I’ve been messing around with reloading for some time but I’ve just now gotten serious as I have a tikka 243 1:8 so no good factory options.

I’m trying to follow Form’s simple method to reloading. Here is my spec:

Powder- H4350
Primer- CCI200 LR
Brass- Starline 1x fired and resized to bump shoulder back
Bullet- 108 ELDM
Coal- 2.8

I made up 2 to shoot and check for pressure at and just under book at 42 and 41.5 grains of 4350

I shot them both and velocity was 2844 with 41.5 and 2899 with 42 grains. I got some stiffish bolt lift then upon inspecting, I’m seeing some slight ejector marks. Here are the pics of the brass:

a8cf670efadf305faf8bb8a019d10463.jpg

31af3eb9c5b0eb46a27b3990fe4acb15.jpg


Do either of these look bad enough to not continue? I’m tempted to just run with the 41.5 grains but the bolt lift has me slightly nervous. I’ve felt stiffer bolt lift than this tho… and it was 1 round so my pea brain didn’t really make a mental note of how stiff it was.
 
Hodgdon shows 41.1 max load for .243 108eldm and H4350 @ 2.7 OAL. 59kpsi.

A quick check in Quickload shows 42gr, 2.8" oal at 60kpsi and 2700fps (assuming whatever case capacity is default for .243 in QL is correct - 54gr is what is in there).

I think the combo of the 2900fps velocity, obvious signs of pressure, and being over the book max would all give me pause going up.


I would be interested in COAL with bullet in the lands, magazine limitation on COAL, and average h2o capacity of your fireformed and sized brass. These would all help put some bounds on what you're after.

Short answer - it's hot go down.
 
Hodgdon shows 41.1 max load for .243 108eldm and H4350 @ 2.7 OAL. 59kpsi.

A quick check in Quickload shows 42gr, 2.8" oal at 60kpsi and 2700fps (assuming whatever case capacity is default for .243 in QL is correct - 54gr is what is in there).

I think the combo of the 2900fps velocity, obvious signs of pressure, and being over the book max would all give me pause going up.


I would be interested in COAL with bullet in the lands, magazine limitation on COAL, and average h2o capacity of your fireformed and sized brass. These would all help put some bounds on what you're after.

Short answer - it's hot go down.

So I have struggled to measure lands on this rifle a bit. I used a Hornady comparator with the dumby case and a 108 and put a cleaning rod through the muzzle and went back and forth a dozen times and finally landed on 2.225 CB to OG. Looking at the COAL of that, it was 2.814 so I just did the easy thing and backed to 2.8 and called it good enough.
 
Stiff bolt lift means either you're too hot, web of case has expanded too much, or case is not gripping chamber walls for some reason and you're getting a lot of bolt thrust. Unless velocity is lower than expected or you have reason to believe something else is at play, id bank on it being pressure.

Your velocity with an 18" barrel indicates there is not a lack of pressure.
 
I’ve been messing around with reloading for some time but I’ve just now gotten serious as I have a tikka 243 1:8 so no good factory options.

I’m trying to follow Form’s simple method to reloading. Here is my spec:

Powder- H4350
Primer- CCI200 LR
Brass- Starline 1x fired and resized to bump shoulder back
Bullet- 108 ELDM
Coal- 2.8

I made up 2 to shoot and check for pressure at and just under book at 42 and 41.5 grains of 4350

I shot them both and velocity was 2844 with 41.5 and 2899 with 42 grains. I got some stiffish bolt lift then upon inspecting, I’m seeing some slight ejector marks. Here are the pics of the brass:

a8cf670efadf305faf8bb8a019d10463.jpg

31af3eb9c5b0eb46a27b3990fe4acb15.jpg


Do either of these look bad enough to not continue? I’m tempted to just run with the 41.5 grains but the bolt lift has me slightly nervous. I’ve felt stiffer bolt lift than this tho… and it was 1 round so my pea brain didn’t really make a mental note of how stiff it was.

I’d bet lunch those loads are about a good stopping point, but not over pressure. Every brand of brass is different, but for what you have there the primers aren’t super flat or leaking and the ejector mark that pronounced isn’t uncommon.

If they only last 5 reloads before the case head starts to separate or the primer pockets open up then I tend to think it’s too much pressure to be reliable, while most of my loads that can survive 10 shots on each piece of brass look much like what you posted.
 
Having said that, one case of each powder charge can be deceiving. I’d mark those cases so you can keep track of each to see how long they survive over time.
 
I’m not sure if you have already tried it with unsatisfactory results, but if looking for some more speed I would work up 47-48gr H1000. Hodgdon max is 49.2gr
I get better speed than H4350 and don’t have to push it.

Edit:
I’d have to dig around a bit, but it seems more guys have had trouble with that combo in 243win at the top end. Then being conservative and bumping down and running it around 40-40.5gr
 
I’m not sure if you have already tried it with unsatisfactory results, but if looking for some more speed I would work up 47-48gr H1000. Hodgdon max is 49.2gr
I get better speed than H4350 and don’t have to push it.

It just so happens I have some h1000 so I can try some. I know I’m not supposed to ask strangers on the internet this but how many grains of h1000 did you land on?
 
It just so happens I have some h1000 so I can try some. I know I’m not supposed to ask strangers on the internet this but how many grains of h1000 did you land?

Asking is never the problem, it’s assuming you can just load up and do the exact same with no testing is where things can get exciting.

I’d work up to 47-48gr. I’ve landed on 47.5gr for now and have shot that load and 47gr the most. 50 rounds each.

Mcgowen 8tw 243win standard chambering 22” barrel
47.5- 2978fps avg
47-2936fps avg

48 got me over 3k but have not loaded and shot that one enough to really validate it. But other 2 have hovered around that 1.2-1.4” 10 shots groups.
I’m using Starline brass as well for those loads
 
I’ve been messing around with reloading for some time but I’ve just now gotten serious as I have a tikka 243 1:8 so no good factory options.

I’m trying to follow Form’s simple method to reloading. Here is my spec:

Powder- H4350
Primer- CCI200 LR
Brass- Starline 1x fired and resized to bump shoulder back
Bullet- 108 ELDM
Coal- 2.8

I made up 2 to shoot and check for pressure at and just under book at 42 and 41.5 grains of 4350

I shot them both and velocity was 2844 with 41.5 and 2899 with 42 grains. I got some stiffish bolt lift then upon inspecting, I’m seeing some slight ejector marks. Here are the pics of the brass:

a8cf670efadf305faf8bb8a019d10463.jpg

31af3eb9c5b0eb46a27b3990fe4acb15.jpg


Do either of these look bad enough to not continue? I’m tempted to just run with the 41.5 grains but the bolt lift has me slightly nervous. I’ve felt stiffer bolt lift than this tho… and it was 1 round so my pea brain didn’t really make a mental note of how stiff it was.
For that load, drop down and try 40 and 40.5.
 
This is exactly why when I do the painless method I start 2gr below the avg book max and shoot a short pressure ladder to see if pressure shows up. Changing the COAL and getting closer to the lands will change the peak pressure point and make a difference there alone.

Pronounced ejector marks, bolt lift, and velocity of that barrel length prove you're definitely up there. Some brass is softer and shows ejector marks easier, but I agree with everyone else that those are probably on the ragged edge, and IMHO 40-40.5gr would probably be closer to where you need to be for a safe hunting load that won't get potentially disastrous if you get any moisture on a case.
 
It just so happens I have some h1000 so I can try some. I know I’m not supposed to ask strangers on the internet this but how many grains of h1000 did you land on?
H1000 seems too slow for an 18" barrel in this case... Prob best between 4831 Rl16 burn rate.
 
H1000 seems too slow for an 18" barrel in this case... Prob best between 4831 Rl16 burn rate.
The idea that you are not getting a complete burn with the slower powder, therefore not getting velocity you would otherwise get running a longer barrel?

Asking genuinely because I have no experience with short barrels and slow powders so I only know what I know.
 
The idea that you are not getting a complete burn with the slower powder, therefore not getting velocity you would otherwise get running a longer barrel?

Asking genuinely because I have no experience with short barrels and slow powders so I only know what I know.
Correct. Slower powders are only good when there's enough barrel to burn them
 
Correct. Slower powders are only good when there's enough barrel to burn them

I threw 46 gr in 5 rounds to see what it would do - not bad considering I was on a pretty improvised rest.

bac52a5388dab024fcc8e3b033655a7f.jpg

41b77b571e74087553b73a422f39c201.jpg


It’s definitely slower than 4350 - 41.5 of 4350 is 120 fps faster. But it didn’t shoot quite as tight but I’m not gonna blame that on the load…. I was in a hurry.

I didn’t get any pressure signs with the h1000 but I had to def crunch some powder when I seated my bullets.

The good news is I shot 5 rounds of 4350 at 41.5 today and I had no heavy bolt lift or bad extractor marks so I’ll probably roll with it.
 
I threw 46 gr in 5 rounds to see what it would do - not bad considering I was on a pretty improvised rest.

bac52a5388dab024fcc8e3b033655a7f.jpg

41b77b571e74087553b73a422f39c201.jpg


It’s definitely slower than 4350 - 41.5 of 4350 is 120 fps faster. But it didn’t shoot quite as tight but I’m not gonna blame that on the load…. I was in a hurry.

I didn’t get any pressure signs with the h1000 but I had to def crunch some powder when I seated my bullets.

The good news is I shot 5 rounds of 4350 at 41.5 today and I had no heavy bolt lift or bad extractor marks so I’ll probably roll with it.
Sure, The powder is too slow to get enough in the case to make pressure before the bullet is out of the barrel. You got a decent group, but one group from a load with high SD's would not give me much confidence. If you don't plan to shoot very far the load could be great though.
 
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