Crimping rifle rounds

[Deleted member 107796]

I thought I'd add something. The new types of very slow burning powder will minimize the effect of the need for consistent ignition of faster powders, which a crimp will achieve. The data presented in the previous post, which I like, has a test condition worth mentioning, which is "what type of powder was employed?"

Also, very short throated cases, like the WSMs I mentioned, don't have a lot of surface area to grab the bullet and I've seen bullet slippage in non crimped loads, from not so much force. Both are considerations for crimping or not.

 

[coop2564]

I just started crimping (lee factory crimper) my 6.5cm and my 270win. Reason I had my 270 which are compressed loads slipping out some shooting in mag under recoil. Thing I noticed most was increase in pressure and speed using crimped. at my normal load was seeing pressure, hard bolt lift, flat primers, this was with med crimp backup off 1 gr back to same velocity and pressure gone. It also decreased my ES slightly and saves some powder to get same velocity. I see more benefit than negativity.

 

[theosmithjr]

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

The Cannular on a BULLET is for CRIMPING! I would NEVER RECOMMEND crimping, if the BULLET DOES NOT have a CANNULAR! THATS WHY it's There in the 1st. Place! Also Die Sets DO NOT COME WITH A CRIMPING DIE, UNLESS there's a NEED TO CRIMP! IF the DIE SET for the CALIBER. you're loading DOESNT COME WITH IT, and the BULLET you're Loading DOES NOT HAVE a CANNULAR, WHY on GODS EARTH WOULD YOU EVEN CONSIDER CRIMPING IT?
Theosmithjr

 

[theosmithjr]

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

Because the ones I was referring to are SINGLE SHOT BOLT ACTION. NO CLIP, NO MAG. JUST a Floor Plate. Even in my .338 Lapau Mag. THERE IS NO NEED TO CRIMP!
NOW if I was BANGING OUT 30 - 40 rounds in RAPID FIRE MODE, that's a COMPLETELY DIFFERENT STORY IN ITSELF! Theosmithjr

 

[coop2564]

The Cannular on a BULLET is for CRIMPING! I would NEVER RECOMMEND crimping, if the BULLET DOES NOT have a CANNULAR! THATS WHY it's There in the 1st. Place! Also Die Sets DO NOT COME WITH A CRIMPING DIE, UNLESS there's a NEED TO CRIMP! IF the DIE SET for the CALIBER. you're loading DOESNT COME WITH IT, and the BULLET you're Loading DOES NOT HAVE a CANNULAR, WHY on GIDS EARTH WOULD YOU EVEN CONSIDER CRIMPING IT?
Theosmithjr

To get a more consistent ignition, better ES, to prevent bullet slip both on compressed loads and mag slip of hard kicking loads, to eliminate varying neck tension, etc.. You do not have to have a cannular to crimp with the Lee factory crimper, it creates one.

 

[coop2564]

Lee Factory Crimp Die crimps your bullets in place the same as factory ammo. A collet gently, but firmly squeezes the very end of the case into the crimping groove, exactly the same as factory ammo.

• Gives a segmented straight crimp, and crimps more firmly than any other tool
  
  
• It is impossible to buckle the case as with regular roll crimp dies
  
  
• Necessary for hunting and combat. Ammunition will be more accurate and better able to withstand rough handling because the bullet is firmly crimped in place.
  
  
• Tests demonstrate that even bullets with no cannelure will shoot more accurately if crimped in place with the Lee Factory Crimp Die. A firm crimp improves accuracy because pressure must build to a higher level before the bullet begins to move. This higher start pressure insures a more uniform pressure curve and less velocity variation. Even powder selection is less critical. Until now, handloaders seated the bullet to touch the rifling to achieve similar results. This is not always possible nor desirable.
  

 

[theosmithjr]

To get a more consistent ignition, better ES, to prevent bullet slip both on compressed loads and mag slip of hard kicking loads, to eliminate varying neck tension, etc.. You do not have to have a cannular to crimp with the Lee factory crimper, it creates one.

I UNDERSTAND THIS! I said ON MY SINGLE SHOT RIFLES! I've NEVER HAD IGNITION PROBLEMS on ANY LOAD in over 50+ years! ONCE I FIND PERFECTION, I DONT PLAY WITH IT! IF IT AINT BROKE, IT DONT NEED FIXING!
CRIMP ON FRIEND! CRIMP YOUR HEART OUT! Theosmithjr

 

[243winxb]

When looking at the link--

The air space left in the case, along with the type of powder, caused the firing delays. (see conclusion)

If components were different, the crimp would not be needed. Imo.

Doing your own testing is the only way to know.

 

[243winxb]

Lee Factory Crimp Die - Don't over do it.

Got to love internet photos.

 

[theosmithjr]

Lee Factory Crimp Die - Don't over do it. View attachment 126484
Got to love internet photos.

EXACTLY! I personally Invested in Custom made dies from my REAMER on a few Calibers, and from FIREFORMED BRASS! All mine are within .0001 or .0002, No CRIMPING DIE IN THE WORLD IS GONNA GET BETTER THAN THAT! Infact my advice to EVERYONE following this THREAD; is to pay closer attention to your CASE PREPERATION, and INVEST in some GOOD DIES, and to HELL with CRIMPING SINGLE SHOT LONG RANGE RIFLE ROUNDS! GOOD PROPER CONSISTANT NECK SIZING will produce PROPER NECK TENSION using GOOD DIES, the Same BULLET and CASE TYPE when loading. I weigh and sort all my brass. I guage it INSIDE & OUT! I TURN MY NECKS, and guage their run out. When all PASS my PREPERATION STANDARDS, I LOAD! I've NEVER crimped a rifle round in the calibers I shoot. I've NEVER had powder ignition problems! I do have a stack of BEN FRANKLINS that says MY HANDLOADS will CONSISTANTLY MATCH and OUT PERFORM ANY CRIMPED RIFLE ROUND! That's as PLAIN, BLUNT and TRUTHFUL as it gets fellas!
Theosmithjr

 

[theosmithjr]

Lee Factory Crimp Die - Don't over do it. View attachment 126484
Got to love internet photos.

Makes ya WONDER JUST HOW MUCH EFFECT IS ON THOSE DEFORMED ROUNDS AT 100 YARDS! LET ALONE 1000 YARDS OR A MILE! WONDER IF RAMBO TAKES THE TIME TO CRIMP HIS ROUNDS? ****, I WONDER!
Theosmithjr

 

[theosmithjr]

Lee Factory Crimp Die - Don't over do it. View attachment 126484
Got to love internet photos.

Pityful, Discraceful way for a BEAUTIFUL HPBT MATCH BULLET to end up! LOOKS LIKE the Lee Factory Crimp Die is the DEADLY HEROIN of BULLETS! LMFAO
Theosmithjr

 

[Dry Heat?]

I would imagine that the Lee Factory Crimp Die, like all Dies, are user-adjustable. Looks like someone over-did it and nothing more. I've pulled Bullets that I just barely bumped with standard RCBS & Redding Dies and never deformed even a NBT. I just Screw the Die down to the case mouth, lower the Ram and adjust down 1/16 or so of a turn and lock it in. Never had a problem and it gives a smidge of assistance to that case neck tension everyone thinks is adequate. It's worked for me for 44 years now.

 

[cajun]

My own informal testing with AR's in 6.8 and 6.5 revealed that a medium crimp with the Lee FCD reduced sd and es. Several members of the various AR forums have reported similar results.