Would this be considered cratering on a primer?

[chutestrate]

I am using 7.7gr of Bluetooth under 124gr fmj in a p365xl. Has way more bark than my other reloads. I don't like the way they look. First time I'm seeing my primer look this way. 320106

[Recycled bullet]

I think you will be better satisfied with power pistol compared to Blue Dot. I used to use 8 g of blue dot with 115 g full metal jacket back when I first started handloading 9 mm. Blue dot gave me poor performance at anything less than 90% case fill. Power pistol can be significantly reduced and still provide good accuracy and functionality of the handgun. What is your overall length, are all of the brass the same headstamp, and did you try it in a different gun, what primers are you using?

[chutestrate]

These are mixed brass stamps and im using ginex primers or may use ginex primers. Had one failure to ignite after two strikes. These are just range loads I'm assembling. I tested 12. I'll have to see if I have power pistol. If not I have titegroup unique sport pistol aa7 maybe another. Have had bluedot a long term. Thought to use it up buuut now not so sure

[Recycled bullet]

Man load some up with unique -unique is really good with 9 mm and 124 g.

[chutestrate]

Yeah after this test batch I think im going too

[littlejack]

You can overload with any powder. I've seen many primers in that condition with proper loads. It could be the firing pin hole is a little oversize.

[chutestrate]

I was .2gr under max. I think I'm just going to go with my gut. The case was very full, the bark and the primer just worry me. Think I'll go with another powder. This is just a range load anyway.

[BLAHUT]

You can overload with any powder. I've seen many primers in that condition with proper loads. It could be the firing pin hole is a little oversize.

Looks like it came out of a Remington 700 bolt gun....Standard appearance for them... Relieved firing pin hole ??

[chutestrate]

Nothing special. Just a 9mm w/ ginex primer out of a sig p365xl

[Gtrubicon]

Man load some up with unique -unique is really good with 9 mm and 124 g.
I’m getting ready to start load development today with this exact combination for my sons new Ruger PC carbine. I load about every other caliber you can think of but haven’t done 9mm. I’d love to make a good load with unique as I have plenty. Could you pm me what’s worked for you?

[Recycled bullet]

Nothing special. Just a 9mm w/ ginex primer out of a sig p365xlBlue Dot turned my CZ into a flamethrower blast cannon , the blast and concussion may be normal when used in 9mm.

I found it to be extremely accurate and powerful and cycle very authoritatively. My concern was that the slide velocity may have been too high and could have been battering my gun.

It looked and sounded like in between 40 and 10 mm when I was shooting it. I liked to do rapid fire drills at close range paper plates targets it was a lot of fun, the targets runners could be set to turn on edge with a timer then they would turn and face you and you shoot for x amount of time then it would turn on edge again.

I used several pounds of blue dot doing this it worked very well.

I wonder what ballistic improvements could be noticed firing this load through a carbine? The load that I was using was eight grains of blue dog with 115 Grand Everglades ammo FMJ hollow base set at 1.1 " overall length.

I don't think your primers look unsafe. However if it was me I would try using a particular head stamp and see if you get consistent results. Do all of your primers look like this?

[Recycled bullet]

I’m getting ready to start load development today with this exact combination for my sons new Ruger PC carbine. I load about every other caliber you can think of but haven’t done 9mm. I’d love to make a good load with unique as I have plenty. Could you pm me what’s worked for you? I was loading very short overall length 1.1" then I slowly incremented up the powder charge from start I ended up midway between middle and Max from the Lee book I can try to look at that later I don't remember that one off the top of my head and I do not want to give you an unsafe powder charge or load combination.

[Winger Ed.]

As crisp & clean as the edges are around the firing pin strike 'ridge' for lack of a better word,
My guess would be the hole the firing pin comes through is a little too 'generous'.

Any chance you could fire a couple in another pistol?
That might confirm the problem or point you in the right direction.

[WRideout]

I had primer ridges from my FEG 9mm, even with mild book loads. The gunsmith told me that it was the edges of the firing pin hole being relieved (kind of like a glock?) Slow powders, a la Blue Dot tend to work best at full pressure. Therefore, noise and blast may be excessive from a short barrel. I would try any of the medium burn pistol or shotgun powders; Green Dot, unique, etc. I use Promo/Red Dot exclusively in 9x19. It's what I have the most of, and seems to fill the bill very well.

Wayne

[fredj338]

Yeah that isnt really a cratered primer. The bark is a slow powder on a short bbl.
So is it BlueDot or TrueBlue? If its TB, you are pretty far over book.if its BD, you are close or ver depending on data.

[Kosh75287]

My experience with 9mmP is semi-extensive. My experience with Blue Dot in 9mmP is NOT extensive, but it quickly became clear to me that it was at its best with projectiles weighing OVER 125 gr. With 147 gr. TCs, it worked QUITE well. I tend to reserve whatever Blue Dot I can scrounge for use in .38 Super, where it performs as well as anything I've tried, especially with 147 gr. TCs.
I strongly agree with the advice of RECYCLED BULLET, to try Unique with 124/125 gr. bullets. Alliant lists 5.8/Unique/124 gr. Speer GDHP as a maximum load, with 1.12" c.o.a.l. Alliant clocked it at 1180 f/s from a 4" barrel, which is solid performance for this round. At the near-max/max chamber pressures generated by loads in this realm, Unique will also burn far more cleanly than its reputation may predict. Unique DOES have a reputation for creating a fair amount of muzzle flash, so you might not notice much reduction from Blue Dot. If loads with Unique do not perform in a way that you like, MY next move would be to try a work-up with Power Pistol. If neither Unique nor Power Pistol work well for you, I'd suspect that something else is going on.

Forgot to add: The primer in your image does not look worrisome, to me. I'd be far more concerned if the primer edges were flattened, AND you had the little raised portion near where the firing pin strikes.

[405grain]

chutestrate: I'm going to have to assume that you're talking about Blue Dot since there is no such thing as Bluetooth (in less your gun has a wireless connection). If you are using Blue Dot in that load there is the very real possibility of you having a pressure issue. I ran the information that you presented through GRT. You didn't say what actual bullet you were using so I chose the Hornady 124 grain RNFMJ. You stated that your load was 0.2 grains below max. You are correct; your load is 0.2 grains under the absolute Pmax for that cartridge!! Yes, you are seeing signs of over pressure!

Assuming a 4" barrel your load would be giving a velocity of 1161 fps, at a pressure of 31,839 psi. That's an assumption because Blue Dot is one of a few powders that experiences an exponential rise in pressure once it approaches it's top listed loads. I don't know where you got your load data from but at 7.7 grains with a 124 grain bullet I get the following warning message: "Can lead to unexpected pressure peaks". You would be much better served if you lowered your powder charge a half grain to 7.2 grains, which is the highest charge weight for that load data that doesn't have a warning caution associated with it. with a 4" barrel 7.2 grains of Blue Dot and a 124 grain bullet would give you 1087 fps at 26,053 psi. The correct charge of Blue Dot would make shooting your pistol both more enjoyable, and safer. If you do choose to switch to a different powder, please do not start out with loads near maximum. Start around mid range, then increase slowly, and back off once you see pressure signs like the ones in the photo you posted.

[chutestrate]

Thank you everyone. I did fat finger the powder name...it's Blue Dot. I started midrange, and worked up to the 7.7gr of Blue Dot. I did want to an upper range load, but didn't like what I saw with Blue Dot. I went to Unique, and am happy with the results. I worked my way up with some test loads to 5.8gr of Unique, and I'm back down at the upper midrange. I wanted to mess around with some higher performance rounds instead of my mild target loads. i appreciate eveyone's patience with my questions. It was fun experimenting for a couple of days. I'm using RMR fmj's to load these. As I worked up to 5.8 gr of Unique I didn't see any pressure signs like I did with Blue Dot. I'm back down at 5.5gr of Unique for my loads. It's got a little pep, and seems to be fairly accurate.

[Hickok]

I have 3 Sigs in 9mm, and they all leave primer marks like you have pictured. Normal.

The older Glocks left a vertical hash mark on the primer, but the newer Gen 5's leave a teardrop shape on the primer.

From what I have researched, the reasoning is to prevent the firing pin tip from getting broken. The crater or puckered primer-cup allows the firing pin tip to be pushed back slightly before the slide starts the ejection process. The face of the slides are chamfered to allow this.

Ak-47s and Ak-74s both have this type of primer cup dimple after firing.

Remington got this bright idea for awhile in their Model 700 rifles. The bolt face had a bevel or chamfer around the firing pin hole and the primer always came out looking like an over pressure load. I contacted Remington about this on two 700's I bought before they went bankrupt. They were purposely doing this and said it was normal and no problem. I thought it sucked on a bolt action rifle.

As to 9mm pistols, this is completely normal. (Not to say you can't overdue a load and get a extreme pressure signs)

I can pick up shot 9mm cases and many times tell what brand of pistol they came out of.

[fredj338]

IF you want to max out the 9mm+p, try AA#7 or HS6 or Longshot.

[Larry Gibson]

FYI

I have not pressure tested any 124 gr jacketed bullets in the 9mm cartridge. prefer to use 115 gr JHPs [Hornady XTPs or Speer GDs] for my PD rounds. I load them over 7 gr of Herco. That load pressure tested at 33,800 psi [Oehler M43] and runs 1300 fps out of my CZ75 with 4 5/8" barrel.

My standard practice load [Lee 120 gr TC over 4 gr Bullseye] tested at 31,400 psi.

The SAAMI MAP for standard 9mm loads is 35,000 psi.

[44Blam]

Looks a little funky but your firing pin hole may be enlarged - does factory ammo do this?

With BlueDot, your generally gonna have lower pressures in a 9mm because it is a slower burning powder designed for heavy shotgun loads (buck/slug) and cartridges like 10mm/357 mag...

[dverna]

I have a pound of Blue Dot to do some testing in a 9mm carbine. The longer barrel should allow a higher velocity with the slower powder. I have seen some very heavy loads I do not feel comfortable using by Internet idiots trying to get .357 Mag performance from the 9mm using Blue Dot in carbines.

Another thread about potential pressure spikes in cold weather with BD, is concerning. I was looking at +P loadings with 124 gr XTP’s. Might not be such a good idea for use in Michigan.

[Gtek]

Just a thought, could it possibly be unlocking before things calm down in regard to chamber pressure wiping primer? When I first acquired my 365 I ran some Sig 147 HP through it and it smeared the primer on every one very similar looking to yours. Took piece apart and looked everything over, found firing pin hole flush, sharp and tight. Went next magazines with factory Sig 124 Elite and they looked perfect! I was able to speak with a serious Sig fanboy and he said the early 365's along with their other little fixes were unlocking early with heavy or hot loads and a there were some broken strikers because? Short barrel with heavies are not your friend for velocity I would think, I have put over 500 rounds flawlessly through it since that one mag full of heavies with no sign of nothing with the factory lighter side projectiles.