Let the 16 sit for a bit or over night. Unload in the morning and try again. New 365 mags are notoriously stiff and difficult the first couple of cycles. After a couple of days, or a range trip, they’re good to go.

 

Will update after trying your suggestion. Thanks!

 

Cycling the mazazine will do more than loading and sitting. Just keep using them and they will loosen up a bit.

 

And…welcome to the forum. While you wait for the springs to break in- head on over to the new member intro section and tell us a bit about yourself. 😉

 

Try this. Don't push the tongue on the Magula all the way back, pushing towards the bottom of the casing like you would on the other rounds. Push it just past the bullet and catch the top of the casing. This will push the front/top down and allow enough room to insert the final round. Works for me.

At any rate, the spring will loosen up with time and the mag will get easier to load.

 

I highly recommend using this for any P365 magazine.

https://www.speedbeez.com/product/speed-beez-lever-loader-sig-p365-9mm-magazine-loader/

They work better in my opinoon than a Magula UpLULA, especially for the 17-round magazines.

Another suggestion is let the full magazine set for a day or two.

 

My left hand is physically handicapped. This speed loader is absolutely amazing! I loaded 17rds into 6 new mags with very little effort and in just a few minutes!

 

10 17rnd mags loaded with 17 rounds. No issues here. Uplula is my friend. I did take them apart and cleaned/lubricated the inside before loading.

 

I did take them apart and cleaned/lubricated the inside before loading.

This is what I do for 10, 12, 15, and 17 round P365 mags. Especially the bottom of the follower, examining the surfaces and edges for excess polymer or swarf from the manufacturing process. I also swab out the insides of the mag bodies (I use Eezox in a well ventilated area) and look at the springs, for kinking or unusual bends.

It's funny, sometimes even the act of taking them apart and putting them back together helps. I added a couple TTI base pads to a Macro mag recently. One loaded to 20, the other would absolutely not load past 19. I took that one apart wondering what the heck was going on, then afterwards got 20 in, as per usual.

Another option is just shoot the 17 with 16 rounds a couple times. Leaving it loaded for a few days (I do this also) seems to help, or at least not hurt. And maybe as @Swirling Eddy said, technique may play a role. I'd try what he suggested.

Good luck! Keep at it and I think it will be ok.

 

Lots of great advice above.

 

I've been successful using a number of (combined) approaches to new sig P365 mags - which are very well captured in the above posts:

• disassemble the mags and clean them - especially the mag body interior which often comes with some preservative (and look for flash/burrs on the follower)
• apply a coating of dry lube to the inside
• use uplula to load to capacity - and swirlingEddy's tip is a good one. yes, 17th rd is TIGHT
• keep max loaded - but also do a couple of unloads and mag re-loads to cycle the spring

I have 4 new 17rd mags that have started to ever so slightly loosen up per the above process. Out of all my 10, 12, 15, and now 17 rd mags - the 17 have clearly been the tightest (followed by the 15).

 

Greta advice by all. This is a known characteristic of Sig mags.

 

I just picked up a new P365 Macro yesterday. Same problem, although I don't usually load my mags to the max, just a quirk of mine. I will be following.

 

Take a deep breath....then, squeeze your vajina muscles together as hard as you can. Now, suck it up and load that mag sissy!!

 

Edited: duplicate post

 

OP, let us know how your mag loading is going.

Snapped some pics tonight that might help. First pictures are of normal Maglula usage.

Sometimes this doesn't work with very tight new mag springs. But this should:

Insert the tongue just past the bullet onto the top of the casing and press down. This should give you enough clearance to load your last round.

Hope this helps.

 

OP, let us know how your mag loading is going.

Snapped some pics tonight that might help. First pictures are of normal Maglula usage. View attachment 504515
View attachment 504514

Sometimes this doesn't work with very tight new mag springs. But this should: View attachment 504516

Insert the tongue just past the bullet onto the top of the casing and press down. This should give you enough clearance to load your last round. View attachment 504517

Hope this helps.

Thanks for this! I picked one up today. Wish I knew about these years ago! Or, maybe I saw them and thought pshh, who needs one of those, lol. Definitely makes loading easier and faster.

 

Same issue. I even posted about it awhile back. My 17th round went in but was so tight that it wouldn’t even rack into the gun when I discharged the one in the chamber. It gradually did loosen up but took awhile.

 

I had six new P365 micro 10-rnd mags with my new pistol that would not take the 10th round with the UpLULA.

I pushed down on that loader as hard as I could. Close, but No dice.

I read threads stating that in time, these mags will take the 10th round. I was skeptical becuase I did not understand what would happen inside the mag over time to make more room avaiiable for the spring to compress more.

So, I just loaded 9 and enjoyed many range trips.

Then on one range trip, in go 10 rnds on most of the mags. Eventual all.

I still don't understand where the extra room for the spring to compress more came from..

 

Funny how after a few range visits you can load them by hand...

 

I just got my XMacro today! I had no problem putting in all 17 rounds using the Sig ammo helper, that was included!
The gun shot all 34 rounds flawlessly!
Put a little elbow grease in there, Bro!
The Sig loader definitely works! Enjoy Bro!

 

All 4 mags with my new TacOps were probably the tightest mags I've ever loaded. Left them full loaded for a few days before the first trip to the range and they loosened up a bit.

 

yep, I had same experience with the 4 mags I bought couple of months ago. They seem to loosen up just a little keeping them loaded for a while - and shot periodically too. I do suggest you practice racking the slide (starting closed) on a full 17 rd mag. The slide "drag" is noticeable, but with proper technique and a serious effort, it works. However, my 5ft 2 wife could not do it.

 

i just received my new 17 rd mag and same issue. Mine looked like the follower was turning sideways but I will wait a day or so then try again.

 

All I can add is confirm my above post from 5 months ago. All 4 of my 17rd mags have loosened up slightly, but noticeably, after being stored full and shot as well (maybe 80 - 100 rds through each). With significant effort, the uplula did get the 17th round fully in first few times - it is a little easier now (still need the uplula).

 

I personally was able to put all 17 rounds in my x macro. I used the cheap loader sig included. I was able to put the mag in the gun and shoot all 17 rounds with zero difficulty. I purchased my x-macro 3 months ago.

 

I bought two 17 round mags and even though it was difficult, I was able to use my UpLULA and get them all in. I let them sit fully loaded and eventually I'm able to fully load without the help of the UpLULA. It just takes time.

 

After thorough mag cleaning, I was finally able to get 17 rd in all 4 mags. That 17th is still a bear, even with uplula.

 

I work for a police department and just got the P365 as my off duty carry. The guys at my range were telling me the 17 round mag for the P365 is good for range shooting but not reliable in real world application. Can anyone elaborate why they would say that or can share any issues they have had with the new 17 rd magazine. Thanks!

 

I have no clue why they’d say that. Did they give a reason for their opinion?

I have four Macro mags in use, about 500 rounds through them. 2 are stock 17s, 2 I have TTI extendo’s to make them 20. No issues so far.

 

That last round is a bear in some of my XMacro mags. I end up using my Maglula. It's pretty tough, and then the last round will go in. If it continues to be a problem, Call Sig Sauer CS. Maybe they will replace the magazine for you.