Crimping rifle rounds

[theosmithjr]

https://apps.dtic.mil/docs/citations/ADA341390 View attachment 125835

An engineering study was conducted on the 7.62 mm ball cartridge, M80, to determine the cause of a recurring delayed propellant ignition and to identify possible causes of action to correct the problem

Hey your AVATAR, is that a picture of Archer Fred Bear? Theosmithjr

 

[Oxobrianne 272]

I use Lee Collett crimping dies for all my bolt action rifle calibres. I think a light crimp provides consistent ignition. When using a 10 or 20 round mag for tactical target shooting the crimp stops the bullet lower in the mag from moving under recoil.
I use a light crimp even when single loading after the range officer issued an unload command due to target malfunction and my then uncrimped bullet,which was just touching the lands,stayed in the barrel whilst the powder spilt into the action.
For pistol loads the crimp needs to be relative to the cartridge power to prevent the bullet moving and jamming the pistol or moving back and putting the pressure up.

 

[theosmithjr]

I use Lee Collett crimping dies for all my bolt action rifle calibres. I think a light crimp provides consistent ignition. When using a 10 or 20 round mag for tactical target shooting the crimp stops the bullet lower in the mag from moving under recoil.
I use a light crimp even when single loading after the range officer issued an unload command due to target malfunction and my then uncrimped bullet,which was just touching the lands,stayed in the barrel whilst the powder spilt into the action.
For pistol loads the crimp needs to be relative to the cartridge power to prevent the bullet moving and jamming the pistol or moving back and putting the pressure up.

All my rifles are Single shot Bolt Actions. NO NEED TO CRIMP. But I agree with your statement concerning .30 cal and above with clips or mags. I only CRIMP my BIG BOY HANDGUNS. 454 Casull, .50 Desert Eagle, and my .45 Colt Long and my .44 Mag when I HUNT with em. Good, sound advice. Theosmithjr

 

[dfanonymous]

All my rifles are Single shot Bolt Actions. NO NEED TO CRIMP. But I agree with your statement concerning .30 cal and above with clips or mags. I only CRIMP my BIG BOY HANDGUNS. 454 Casull, .50 Desert Eagle, and my .45 Colt Long and my .44 Mag when I HUNT with em. Good, sound advice. Theosmithjr

I'm not agreeing or disagreeing.
Why no need to crimp cartridges in bolt action?

 

[Deleted member 107796]

I've been crimping my magnums (particularly my short throated WSMs) when I use a cannelured bullet as well as for my magnum revolver rounds. In the revolver rounds, it is even suggested for non cannelured bullets, particularly for H110, Lil Gun or other powders which need a stout crimp and magnum primer to assure consistent ignition.

 

[theosmithjr]

I'm not agreeing or disagreeing.
Why no need to crimp cartridges in bolt action?

Single Shot Bolt Action have NO MAGAZINE in which to STACK AMMO, therefore they DO NOT need to be crimpedto prevent Bullet Movement from HEAVY RECOIL.! YOU XAN Crimp ANY BLET that has a Canuliar, If you have a Crimping Due.
Theosmithjr

 

[SidecarFlip]

Semi auto rifles and handguns have a more violent extraction and feed process which is why a large amount of people prefer to crimp.

I like the lee crimp dies personally if you for whatever reason feel the need to have to crimp

Never seen a handgun with 'violent extraction' and I have a lot of handguns. Handgun rounds are typically crimped because the recoil is more abrupt and bullet setback from recoil is more of a possibility.

Extraction on a handgun consists of a manual extractor.

I don't like Lee anything except their collet crimper, which I use on 460 and 500 Smith loads and my 338 Lapua.

 

[Deleted member 107796]

I've never really understood why a cannelure is considered acceptable but a crimp "damages" a bullet.

This is important and is described pretty well in most reloading manuals. My Speer manual has a section on it. "Bullets to be crimped MUST have a crimping groove. The groove provides the needed clearance to allow the crimp to form without damaging the bullet. Crimping an uncannelured bullet deforms the jacket and poor accuracy can result."
As mentioned in a previous post, you can apply a light crimp to an uncannelured bullet but it better be light.

 

[dfanonymous]

Never seen a handgun with 'violent extraction' and I have a lot of handguns. Handgun rounds are typically crimped because the recoil is more abrupt and bullet setback from recoil is more of a possibility.

Extraction on a handgun consists of a manual extractor.

I don't like Lee anything except their collet crimper, which I use on 460 and 500 Smith loads and my 338 Lapua.

If you read the quote I said "more violent extraction"
Key being more. Would you call in a auto loading pistol that uses a browning recoil action whos slide moving to the rear dragging the empty case with the extractor and slamming said casing into the ejector sending it flying out roughly 10 feet away LESS violent by definition then say a rem 700 in .308....where the extractor...helps pull the cartridge as the bolt is manually manipulated at a much lower speed then a handgun, backwards until the tension of the ejector is able to fling the casing slow enough to catch with your hand?

The only manual handgun extractor I know of is this attached.


I'm not a huge fan of lee products too, but as I stated I like their crimping dies over other companies.

 

[Oxobrianne 272]

I always use Lee Collet crimping dies for all my rifle calibres - I feel that they provide a "gentle" firm crimp. I also use Lee's collet neck sizing dies - initially through laziness - no lubing! Using these dies I have totally consistent 1/4 MOA groups from my Blaser LRS 2 using barrels .223, 6.5 x 55, .308 and .300 Win Mag (not used that much as only 98 loads per pound of powder!!) Vitavouri powders and usually Lapua cases. Bullets generally Sierra Match Kings - sometimes Lapua depending on availability. I shoot tactical comps out to 1,000/ 11,000 yes. I switch barrels depending on wind and range. 6.5 x55 is a great all rounder.
N.B. I do use RCBS competition micrometer seating dies.

 

[theosmithjr]

I always use Lee Collet crimping dies for all my rifle calibres - I feel that they provide a "gentle" firm crimp. I also use Lee's collet neck sizing dies - initially through laziness - no lubing! Using these dies I have totally consistent 1/4 MOA groups from my Blaser LRS 2 using barrels .223, 6.5 x 55, .308 and .300 Win Mag (not used that much as only 98 loads per pound of powder!!) Vitavouri powders and usually Lapua cases. Bullets generally Sierra Match Kings - sometimes Lapua depending on availability. I shoot tactical comps out to 1,000/ 11,000 yes. I switch barrels depending on wind and range. 6.5 x55 is a great all rounder.
N.B. I do use RCBS competition micrometer seating dies.

Am I reading right? OUT to 11,000 Yards?
Theosmithjr

 

[Oxobrianne 272]

Am I reading right? OUT to 11,000 Yards?
Theosmithjr

Sorry Theosmithjr. Typo error on smartphone - comma in wrong place - should read 1,100 yds.
I should be so lucky!!!

 

[theosmithjr]

Sorry Theosmithjr. Typo error on smartphone - comma in wrong place - should read 1,100 yds.
I should be so lucky!!!

 

[theosmithjr]

Ok sir, wheeww. I thought I'd awaken from a 20 year nap. LOL
Theosmithjr