Short OAL 38S ammo causing nose dive jams

[bjcollado]

So I recently purchased ammo from another store. Shot a recent match with it and landed with 2 nose dives in my first stage. 2nd stage to next to last, used my leftover ammo from the usual store i buy my ammo from and had no problems whatsoever. Last stage, ran out of old ammo, used the new ammo and had the same nose dive jams. Used 3 different magazine, all the same jams with the same ammo. I just checked the lengths of both ammos, new ones that jam have shorter OAL from the old ones.  Do shorter OAL really cause these kind of jams or should i look at another culprit?

[davsco]

What are the lengths?

[bjcollado]

I forgot what lengths it was, brother. Sorry.  But i think the old ammo was *.450 and the new was *.39 not sure but maybe around that range

[BeerBaron]

What shape are the projectiles? That can change things. But assuming it was 1.2450 to 1.239 that shouldn’t have a massive effect on feeding. All my 38sc guns feed anywhere from 1.230 to 1.250 with 124gn RN bullets. Check the brass too, especially the rim. 

[loubob]

the first thing i would do is check my mags are they within spec?

[cperazza]

A little more info on the ammo would help. 

 

Ammo Brand or are these reloads you are buying? 

 

What is the OAL (you still have some of the ammo or can go to your source to get or ask for a measurement of the ammo)? 

Type of Bullet? RN or JHP? Grain? 

What gun are you using? 

Magazines brand? Have you tuned them and/or check specs? 

 

I am running a 38SC at OAL 1.223-1.228"... Tested 1.234" with no issues. MBX, Atlas, and STI Gen 2 mags minor tuning if any.  

Bullets I have used and are using Zeros JHP 125 gr and PDv1s/PDv2s JHP 124 gr. All 9mm/.355.