Input needed if i am missing pressure signs or not.

The Varget thread mad me start questioning myself. I am now afraid i am missing the pressure signs since i am a new reloader.

These are the top loads i worked up using Varget. and i don't think they are showing signs of over pressure but now am not sure

edt: primers are CCI BR4

27.5 on the left 27.8 on the right.





and a 26.5




any input is appreciated

Look fine to me, but that don't mean squat as reading primers to determine High Pressure is A-kin to reading Tea Leaves. Unreliable at best. Do you have a Chrony? Do you have load data to support your load from more than one source? Are your primer pockets still tight after 3-4 loadings?

Bullet weight?
Rifle?

Now this is a pressure sign and a warning. Or is it?

sorry i did forget to add that info.

Shooting 55g Z-Max out of a RRA 16" mid length AR

I have only loaded once so far so unable to determine if primers are tight after several loadings. So far they are.

the 27.5 and 27.8 both look too hot. you can see the ejector imprint on the cases and brass smearing

if i saw that i would back it down .3-.5 grain where ever the best grouping was.

the best grouping was at 27.8 so i backed it down to 27.5

I did notice the ejector making a mark, but really dident think anything of it since is also does it with factory ammo

All look good, no pressure signs. Photos of Pressure Signs Link

Where did you get your data? Hodgdon lists a Max charge of 27.5gr and Hornady list a Max charge of 26.4gr. You are over the top according to your powder manufacturer and your Bullet manufacturer.

That said, if you are getting "swipe" or extraction marks with factory ammo I would look to the gas system. An over-gassed AR can show signs like my photo above even with the mildest of loads.

to me those are definately starting to show signs of overpressure. The only one that isn't is the Lake City brass which is a 5.56 case origonally. So it's a little thicker from what I've read. Thos ejector swipes and the rim being chewed up can be caused by overpressure but can also be caused by a strong ejector. However, since I don't see it on the lake city brass I'm going with it being from overpressure and the fact your using .223 federal factory brass which is thinner than the lake city 5.56 brass. Again it's better to be safe than sorry.

Those top two loads are warm.

Deep ejector marks and extractor sweeps.

The Gateway thread has a link to a very good writeup about interpreting pressure.

Lyman 49th has it maxed at 27.8 pg 138
but yes hodgdon site has it max at 27.5 as does the canister

What do i need to look for in the gas system?

Your load is too hot.
the bullet maker knows best.
Powder makers may not have tested your bullet, also they want to sell you as much powder as possible.
brass swipes is iffy, but plunger hole marks are high pressure.
unless you have lubed case walls.
just use the hornady load book.

What do the rest of your work up loads look like?

Is the lube off your brass? That can show premature excessive pressure signs.

Those look a little too hot.

Once you can clearly see the extractor and ejector cutouts in the bolt its usually a sign to back off.

And what happened to that brass? Did it get cut short or is it an optical illusion?

Primer is flattened on the case right above the LC case. 27.8gn

The primer as a sole sign is often faulty. Excessive headspace or pushing the shoulder back will appear to be high pressure. When the firing pin hits, it slams the case forward and the primer backs out by the excessive headspace. The pressure rises, causing the cartidge to expand, gripping the chamber. Now the primer protruding out expands. Pressure further rises causing the case to stretch until the head contacts the bolt, flattening the primer and making it look like high pressure.

In .223 Rem, pressure to grip the chamber is around 22,000 PSI. Pressure to elongate the case is over double that but still less than maximum.

Excessive headspace can cause ejector/extractor marks and sweeps are sure signs. It takes about 1/4" of carrier movement to unlock the bolt. The time from the bullet uncovering the port to the bullet exiting the muzzle is about 0.20 milliseconds. The carrier would have to travel at an AVERAGE speed of 100 feet per second to unlock with pressure on the case. That is impossible, carrier initial speed is about 35 feet per second.

These weren't "worked up", they were loaded at max or near max, and maybe over max depending on which load data you use.

To me "working up" means do test loads starting from minimum powder charge and incrementally making some with max powder charge and shooting them in order.

I am only seeing marks on the FC brass. I have been having the same marks with FC brass in 223 and 243 with loads that are not close to max. FC brass is soft, its best to work up your loads with one head stamp or the brass you have most of. I started buying LC brass for the 223 and work up my load with this brass, the FC brass will be loaded and used for storage ammo or I am not able to pick up the brass ammo. I do shoot a few of the other head stamps once I get a load worked up just to make sure its good to go.

Yes, marks can be from the very first firing of factory ammo. Your reloads show no high pressure. Give AR an
antacid.

These are some over max loads that I messed up on awhile back ago. Notice the pierced and flattened primers. I learned my lesson after these.
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So, we have answers of too hot, warm, and no problem in this thread. I'm not knocking anyone on their answers (my first gut feel was they were pretty warm as it looked like the primers were flattened), but this is the thing that scares me with reloading. It just seems like there is a lot of room for interpretation when it comes to identifying what is too hot and what is ok. Because of this, I typically don't load more than 0.5 gr under listed max loads, even if I don't see any pressure signs. I'm sure it's possible I could be giving up a little bit of accuracy, but I'll live with that.

Might seem a bit silly to some, but call me paranoid I guess. I don't have a chrony, either, so can't really look at any data for speed vs chamber pressure for a certain powder. Maybe once I get one, I'll be a little less apprehensive about getting close to max loads.

actually i did work the load up. i just posted pictures of the higher loads to see if they where showing signs or not.

i will post pictures of those when i get a chance this afternoon. I started at 25.8 and went up. I know its not 10% but i feel like 2 grains below max is a good starting point.

Looks hot to me. I'd scrap the brass and rethink your load. Look at your load workup for accuracy with less case deformation. Your reloading process might benefit from a few tweeks but the short and safe answer is to back off that charge weight.

I have 16lb surplus wc846 I wanted to use in my .308 AR10. I got accuracy with similar case deformation to yours even using a tungsten carrier weight. I think my AR10 is over gassed but milsurp ammo does not deform and shoots pretty good. I may get an adjustable gas block for the AR10 but for now the powder is waiting for me to try it with .223 or some other catridge.

How did you manage to get 27.8gr of Varget in an LC case?

fill it to the top

i tested to make sure it was not over compressed

I had to slowly pour it in the cases for it all to fit, if i just dumped it in the funnel it would overflow

Whew. You had me worried there. Based on this thread I wouldn't consider the top two charges in the OP. You might even want to make some another grain lower than 25.8 gr, then go for the most accurate round

I am going with "Warm to Hot". The head face is showing embossing into the ejector pin hole and the extractor groove in the bolt face, and a "swipe" as the bolt face rotates against the case head when the bolt unlocks This means that unlocking is occuring with enough chamber pressure still inside the case to keep some of its grip on the chamber walls Also, a light but noticable crater rim is starting to form on the primer cup where the firing pin strikes. This is caused by the cup face starting to crawl up the firing pin hole in the bolt face. I would call the 27.5 a MAX and begin to go back down in powder to find the most precise or repeatable load for small groups at 100 yd. If you are not willing to trade off speed for precision then the 27.5 is probably where you need to be.

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