COAL and magazine feeding question

[SquarePizza]

Strickly from a feeding standpoint, what would feed more reliably?

1- An overall length that did not use up the entire magazine length,

or

2- A COAL that used up the magazine space available?

 

[BobinNC]

It would have to be #1. Because if you used up 100% of the magazine length available, your rounds would bind.

Ideally you need to leave your rounds about 0.005" to 0.015" short of max mag length, to allow for uneven bullet tips, especially on non-polymer tipped match bullets. Sierra SMK's are notorious for this, even though they shoot real well, the OAL of the SMK's vary as much as 0.015". This is just a byproduct of how they are made, not a lack of QC.

 

[Smokerroller]

I load my SMKs and Amaxs to 2.814 which results in the meplats contacting the magazine wall. No feeding issues yet.

 

[BobinNC]

I load my SMKs and Amaxs to 2.814 which results in the meplats contacting the magazine wall. No feeding issues yet.

If your talking about .308 PMags, per Magpuls website MAX COAL is 2.820", so your still really 0.006" short of full of it....

 

[NevadaZielmeister]

I load my SMKs and Amaxs to 2.814 which results in the meplats contacting the magazine wall. No feeding issues yet.

Hey Smoke,

I could be wrong but all of the rifle rounds in a magazine move forward after the first shot. So really, all of the tips of rifle bullets scrape along the front of the magazine well. I agree that 2.814 is a good C.O.A.L. for the magazines. My AI AW magazines show plenty of room.

 

[SquarePizza]

Just kind of a random at work musing because I have a few platforms that don't make full use of mag space, and feeding isn't always 100%.

One example:

I run a 243 with 85gr SGKs out of AICS mags, they are well short of using up all of the magazine space, and no way to increase the COAL. Every so often a round just plows forward and jams in the mag, rather than getting picked up by the feed ramp.