Do you crimp your home loads?

270Buck

Well-Known Member
I have looked at some older posts on the benefits of crimping rifle ammo.

There seems to be 2 main camps.

Camp 1 are firmly believing that you MUST crimp ammo that is intended for hunting use, the theory is hunting ammo can get some abuse, partly due to the inertia of recoil which can cause the other rounds that are in the magazine to have their OAL shortened.

Camp 2 seem to firmly believe that any round they make does NOT need to be crimped no matter what the intended application is.

I have been crimping my ammo thus far on all my 270 rounds, I have been using a Lee Factory crimp die. I have been getting some great results.

The next batch I make, I will make 10 identical rounds, half crimped and half not. I will then fire a group of each and see what difference it makes. If I remember I will post some photos of the difference (if any).

I am keen to hear what other people do. I have asked all my friends that reload and the jury is still out for me.

Cheers
 
....
The next batch I make, I will make 10 identical rounds, half crimped and half not. I will then fire a group of each and see what difference it makes. If I remember I will post some photos of the difference (if any)...

Whatever approach you use, each load needs to be individually worked up. Your test above will be comparing apples with oranges. I'm sure if you started from scratch with your current brass, powder and bullets you could work up a better crimped load and a better un-crimped load.

It doesn't really matter what you do, as long as you do the same thing every time and you're happy with the results (and they're safe).

Have fun.

JCS
 
Whatever approach you use, each load needs to be individually worked up. Your test above will be comparing apples with oranges. I'm sure if you started from scratch with your current brass, powder and bullets you could work up a better crimped load and a better un-crimped load.

It doesn't really matter what you do, as long as you do the same thing every time and you're happy with the results (and they're safe).

Have fun.

JCS

I realise consistency is key, I am sure I will continue crimping my 270 rounds anyway. Why change or alter a load that I am getting 5 shot groups of 0.5MOA.

I will however be getting my 243 back from being re-built in a few week, hopefully. When I working up a new load I am wondering if I need to crimp or not. I have asked numerous folk and they have differing opinions. Whatever I choose to do it will be consistent.

Cheers
 
I did a sdie by side test on this and found that the Lee Factory Crimp die made not enough difference to the accuracy to be noticeably better but that a standard un-crimped cartridge was just that very, very, slightly more accurate.
 
I did a sdie by side test on this and found that the Lee Factory Crimp die made not enough difference to the accuracy to be noticeably better but that a standard un-crimped cartridge was just that very, very, slightly more accurate.

Very interesting.

What are your thoughts about after taking a shot the rounds being knocked around in the magazine box and thus reducing the OAL?

This is the main point one of my mates stresses, he is in the MUST crimp camp. He claims that he had made a batch of rounds and all had the same COAL, he checked every one. After a few outings after deer and or fox, he out of interest checked the rounds and some had differing COAL. Some rounds may have been in the magazine a few times and therefore have felt the recoil a few times. I cannot remember exactly what difference in length there was but he says it was enough for him to pull the bullets and start again, this time crimping!!
 
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crimping CAN help
so can a lot of things

Try it, if it works and makes them better do it.

I crimp my .222 loads because it tightens the groups up
I crimp my 300WM loads because I want the bullets in the cartridges in the magazine to stay in place!
 
crimping CAN help
so can a lot of things

Try it, if it works and makes them better do it.

I crimp my .222 loads because it tightens the groups up
I crimp my 300WM loads because I want the bullets in the cartridges in the magazine to stay in place!

Fair enough if it works then stick with it.

The investment of crimping dies for all my calibres is what is putting me off!!! I must have some Yorkshireman in me!!!

Also the availability, as the Lee 270 factory crimp die was not the easiest to get hold of.
 
Really depends on application. I do not crimp low recoil cartridges for use in bolt guns or cartridges used single-shots, the exception is for BP cartridges and in that case I normally use a taper crimp. I do crimp (lightly roll crimp) cartridges used in semi-auto's or heavy recoiling cartridges used in bolt guns. Obviously these can suffer from bullet setback from the violence of feeding or the pounding within the magazine from the firing of other rounds. On Revolvers I also crimp to ensure the bullet does not jump forward out of the case and tie up the rotation of the cylinder.

SS
 
On Muir's advice I would have definitely have started crimping a while ago but the nosler 100gr bullets I use don't have the cannelure which I have read in some manuals as essential for crimping. This weekend I'll stack the magazine and leave the bottom round in over a number of firings and measure the OAL before and after out of interest.
 
On Muir's advice I would have definitely have started crimping a while ago but the nosler 100gr bullets I use don't have the cannelure which I have read in some manuals as essential for crimping. This weekend I'll stack the magazine and leave the bottom round in over a number of firings and measure the OAL before and after out of interest.

That would also be an interesting test, I will also do the same.

I will take my callipers out to the field and measure after say 1, 3, 5 and 10 goes in the magazine and see what effect it has. Depending on how considerably the COAL changes I will then decide whether to shoot the "guinea pig" round to see what effect it may or may not have.
 
i dont as i have good neck tension within my case's only ever crimped pistol cases and have no issues.
 
What are your thoughts about after taking a shot the rounds being knocked around in the magazine box and thus reducing the OAL?

If the expander die button on the FL Sizer Die is correct (or spin it in a vice against wire wool) then the neck tension alone will hold bullets in place. If the cartridge has a decent long neck.

I don't know what they do for .300 Winchester Magnum!

And in any decent design rifle the ribs on the side of the magazine hold the carrtidges against their shoulders. I'd only ever use a crimp in a rifle with a tubular magazine as a absolutely mandatory stage as it were. In a hunting rifle I wouldn't bother.

From memory I think that I may have, possibly, lightly crimped the cartridges that I used in Service Rifle events in my 303 Lee Enfield but now can't remember. But if I did that was a standard light roll crimp as at that time Lee's excellent Factory Crimp Dies were not available.

For revolvers I would always crimp but for pistols unless .32ACP or .25ACP I would only ever taper crimp.
 
....I will take my callipers out to the field and measure after say 1, 3, 5 and 10 goes in the magazine and see what effect it has. Depending on how considerably the COAL changes I will then decide whether to shoot the "guinea pig" round to see what effect it may or may not have.

Another approach is to take a loaded round and a marker pen. Mark the bullet neck junction all round and place the marked round in the bottom of the magazine. Don't shoot this round, but keep it there while you fire other rounds at a target. At the end of the session remove the marked round check to see whether or not the bullet has moved in the case neck.

Regards

JCS
 
And in any decent design rifle the ribs on the side of the magazine hold the carrtidges against their shoulders. I'd only ever use a crimp in a rifle with a tubular magazine as a absolutely mandatory stage as it were. In a hunting rifle I wouldn't bother.

Good point - I had forgotten that this is also what struck me when previously looking at this matter and my magazines in the past.

Although I dont want to misquote Muir, I remember him advocating crimping even if potential magazine knock around wasn't a big issue, which I found interesting. http://www.thestalkingdirectory.co....newbie-questions-on-reloading?highlight=crimp
 
On Muir's advice I would have definitely have started crimping a while ago but the nosler 100gr bullets I use don't have the cannelure which I have read in some manuals as essential for crimping. This weekend I'll stack the magazine and leave the bottom round in over a number of firings and measure the OAL before and after out of interest.


its not
None of my bullets have a crimp cannelure except the 130gr, .270 interlocks.....and I seat them longer than the cannelure anyway!

its a light crimp you are putting in not a gut busting curl to the neck edge
 
I've been handloading since the '70s and do not crimp. However, I am careful with neck tension and anneal every five or so firings. All my rifles produce more than acceptable accuracy.
WRT bullet setback, I once kept the same round in the bottom of the magazine of my 416 Weatherby for ten shots and there was no measurable change in length.
Whether crimping produces other benefits, I don't know, I've not found the need to experiment with the technique.
Peter
 
I don't crimp to keep bullets in place during recoil except on handgun cartridges. Bewsher's right. No cannelure necessary if you use a factory crimp die.~Muir
 
its not
None of my bullets have a crimp cannelure except the 130gr, .270 interlocks.....and I seat them longer than the cannelure anyway! its a light crimp you are putting in not a gut busting curl to the neck edge

I don't crimp to keep bullets in place during recoil except on handgun cartridges. Bewsher's right. No cannelure necessary if you use a factory crimp die.~Muir

+1 :thumb:
 
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