How safe is it, not crimping reloads?

[gemini1]

I've recently tried reloading 9x18 mak for my P64. I'm using trimmed down 9mm cases, 93 grain cast from MBC and AA#2.
At one reloading session, I had a few rounds that didn't seat well. There were some lead scraping around the case mouth, guess I forgot to bell those cases or didn't bell it deeper. Anyway, I didn't noticed until after I was done crimping, three of those loads were seated a little too deep. I pulled the bullets, resized the brass and tried to seat the same bullets back. The problem though was, I couldn't seat it at the correct OAL, it went in deeper when I tried to crimp it again.
Being el-cheapo, I didn't want to waste the bullet. So I pulled and load it back after resizing again, but this time I did not apply any crimp, after seating it at the correct OAL. I tried to push the bullet in with my thumb, and I cant get it in, so I guess its tight enough.
When I shot those uncrimped rounds, at 7 yards, I was surprise to get a tight grouping. I took a picture before shooting the rest of my loads, as I figure, the other shots would surely not be as tight. Im not a good shooter, and never have I shot good groupings in one mag dump.
So my question to the seasoned reloaders, can pistol reloads be done without crimping the casings? I know everyone will say crimping is a must for pistols. But if I was able to safely shoot 3 umcrimp loads and got a very good grouping, why not try it again?
Here's my 3 shot group before shooting the rest of my load, which as I predicted, opened up. And I was not able to do again in each mag dump;

[J-cat]

Not crimping is perfectly safe as case tension retains the bullet in the case. Not crimping may cause malfunctions in some pistols.

[Pauliedad]

I try to crimp "just enough" but not too much.
If you're really worried take your calipers to the range and load up a mag. Shoot one round and then check the remaining rounds for set back.
Then shoot two and check the remaining.
Then shoot three and check the remaining.
Then shoot four and check the remaining.
And so on.....
I've yet to experience any set back with even the lightest of crimps. I was mostly worried about .40sw when I first started loading that.

[highpower790]

I never crimp.For what I do its not necessary.All you really need is 2thou of neck tension...that's the difference between bullet diameter and inside diameter of case.This works for me,your application may be different.

[slopoke]

Just remember that all you are doing is removing the belling that you gave the case mouth. It's not for holding the bullet in the cartridge.

[micro911]

All of my rifle reloads are not crimped.

All of my pistol reloads are crimped to a certain degree.

[350skylark]

Just be weary when doing revolver rounds Ive heard that bullets can back out and jam up the cylinder

[M1NM]

Not crimping may cause malfunctions in some pistols.

and those rounds that chamber on the front edge may malfunction if over crimped

[Coyotegunner]

Some experience with crimping I have ran onto over 40 years:

Rifle:Not really a big deal unless caliber is large.
Box magazines with say 3 rds in them when fired,I have noticed bullet set back by the time I get to the last bullet or two.
338 Win Mags are known to seat the bullets deeper with factory,new, crimped ammo.My Ruger 77 was horrible for recoil.My 300RUM is pretty much a bullet seater as well in the box magazine.
Semi autos like ARs not that big of a deal either unless you are loading and unloading the same rounds a bunch.Recoil is not so intense as to drive them into the brass.
I make sure all lube is removed from the brass as well.I also have been known to polish a little off the expander ball to get the bullets tighter.Like in that 300RUM.

Pistol:I crimp them all.Why,because when I was trying to not do it,I would run into that one particular gun that would not feed the bullet into the chamber.Like the load that will feed into a sloppy *ss Glock or XD will not chamber in a Kahr with a match chamber.High end 1911s will not always chamber either if not crimped.Match chambers?
Next I have had the issue with the steep feed ramp of most handguns.Crimping eliminates any issue I may have later.

I use a progressive so it is no issue with the crimp stage,but when it was old school single stage I decided to crimp all pistol.

The last thing I want is a gun that will not go into battery with my loads or factory one's.Or.Have a bullet seated deeper.

Just my opinion.
If not crimping is working for you,then go for it.
Since you got good groups without crimping,I would experiment with seating depth and still crimp.
I just went through a seating depth/how much crimp, issue awhile back for 10mm loads.I resolved finally that 2.5" groups at 50 yds were not going to get any better.Also backed off the powder charge a tad from trying to be top of velocity.
I love reloading.Each gun is kind of a experiment.

[the86d]

If for HD/SD rounds, I'd worry about bullet setback, over time re-chambered rounds get setback a small amount.

If they are never going to be chambered in a semi-auto until ready to be shot, more power to you.

[AandO]

Just remember that all you are doing is removing the belling that you gave the case mouth. It's not for holding the bullet in the cartridge.

Agreed

Minimal belling means minimal crimp means very long brass life.....

[Voo]

Your sizing die should provide the correct case tension to hold the bullet in place. If you're using a crimp die to hold the bullet, something isn't quite right. For me, the main purpose for crimping is to remove any belling created at the powder charging station.

As experienced by other posters, if you don't crimp, you can have issues with out of spec ammo not going into battery. My Glock34 has an incredibly loose chamber and I can get away with not crimping (I still use a LEE FCD just to be sure). My STI Sentry barrel is realllllly tight and almost all of my reloaded ammo fails to go into battery if I don't crimp it. But then again, I'm barely crimping..I'm just using enough crimp to remove the belling..

[gemini1]

So if I drop/insert manually, my uncrimp reloads in my pistol chamber and it slides right in, then Im GTG?
I dont plan on reloading rounds for HD/SD, my reloads are strictly for plinking/target practice. So it will only be chambered once, and be shot at the range.

I try to crimp "just enough" but not too much.
If you're really worried take your calipers to the range and load up a mag. Shoot one round and then check the remaining rounds for set back.
Then shoot two and check the remaining.
Then shoot three and check the remaining.
Then shoot four and check the remaining.
And so on.....
I've yet to experience any set back with even the lightest of crimps. I was mostly worried about .40sw when I first started loading that.

Paul, bullets still in the mag will set back even if not yet chambered? Does the recoil/vibration from the pistol being fired strong enough to do this?

[gemini1]

Your sizing die should provide the correct case tension to hold the bullet in place. If you're using a crimp die to hold the bullet, something isn't quite right. For me, the main purpose for crimping is to remove any belling created at the powder charging station.

As experienced by other posters, if you don't crimp, you can have issues with out of spec ammo not going into battery. My Glock34 has an incredibly loose chamber and I can get away with not crimping (I still use a LEE FCD just to be sure). My STI Sentry barrel is realllllly tight and almost all of my reloaded ammo fails to go into battery if I don't crimp it. But then again, I'm barely crimping..I'm just using enough crimp to remove the belling..

Voo, I also use the Lee carbide FCD. The video instructions to set it up, is to turn the adjustment screw a half turn. So for light crimping, how much do you turn the adjustment screw? would 1/4 turn give it a light crimp? When I set the FCD per instructions, I dont really check my crimped loads meticulously.

edt. Looks like both my pistols chamber is not tight like the others. I just did a plunk test on 5 uncrimp loads for my 9mm Luger, and on the P64. All rounds slide in smoothly.

[energizer]

I've recently tried reloading 9x18 mak for my P64. I'm using trimmed down 9mm cases, 93 grain cast from MBC and AA#2.
At one reloading session, I had a few rounds that didn't seat well. There were some lead scraping around the case mouth, guess I forgot to bell those cases or didn't bell it deeper. Anyway, I didn't noticed until after I was done crimping, three of those loads were seated a little too deep. I pulled the bullets, resized the brass and tried to seat the same bullets back. The problem though was, I couldn't seat it at the correct OAL, it went in deeper when I tried to crimp it again.
Being el-cheapo, I didn't want to waste the bullet. So I pulled and load it back after resizing again, but this time I did not apply any crimp, after seating it at the correct OAL. I tried to push the bullet in with my thumb, and I cant get it in, so I guess its tight enough.
When I shot those uncrimped rounds, at 7 yards, I was surprise to get a tight grouping. I took a picture before shooting the rest of my loads, as I figure, the other shots would surely not be as tight. Im not a good shooter, and never have I shot good groupings in one mag dump.
So my question to the seasoned reloaders, can pistol reloads be done without crimping the casings? I know everyone will say crimping is a must for pistols. But if I was able to safely shoot 3 umcrimp loads and got a very good grouping, why not try it again?
Here's my 3 shot group before shooting the rest of my load, which as I predicted, opened up. And I was not able to do again in each mag dump;

I do the same, just use different powder.

I use 9x19 case, flare it, re-size it, trim it, flare it again, charge it and then seat the bullet.

I use the lee pistol 3 die set so no extra crimp step.

I just tried about 50 of those loads in a P64 and I saw no issues.

Only issue I see is to find my spent casings as it is not pleasant for me to trim 1mm. I may have to improvise my trimming process.

If you come down to South Bay, I can give you couple of my loads.