I recently built a 9mm 1911 using a Para slide frame and barrel. Gun is super tight and smooth, but i am getting  bulged brass using both  factory and my 127 power factor match ammo. It's   also showing flat primers and ejector marks and the brass isnt fully   supported  at the ramp. I'm  thinking the chamer is too short but not sure. Its more of a problem with a 14 lb return spring than it is with a 10 lb as my match ammo didnt show high pressure signs with the 10 lb.
Thoughts?

Headspace gauges?

I'm no gunsmith but it does sound like a short chamber

IIRC off the top of my head, schuemann/(SVI? I think they make the SVI barrels?) barrels are sent with short chambers, up to you to finish them

My thought too
 dont have

Best get.

Changed the extractor, lessened the problem. Not bulging factory ammo. Still buldging reloads which are very soft in my Glock, but longer than the factory, kinda tell me its a throat issue, as in  chamber is short.

last one I'm building  for a long long time.

Good thing.

Without headspace gauges you have no idea what the H you are producing.

Take the bbl out of the 1911. Get a piece of 9mm brass and run it thru your sizing die. Drop the brass in the bbl (plunk test). If you have a "short chamber" the brass will not drop all the way in.

An easy way to measure how long your chamber is. Put a piece of sized 38spl brass in the 9mm chamber, push it in until it bottoms out and mark it with a knife. Pull the 38spl brass out and measure from the end ofthe case to the knife scratch. Then measure where that measurement lands on a 9mm case. Or simply hold the 38spl case up and put a 9mm case (mouth to mouth) next to it and line the end of the 9mm case up with the scratch line in the 38spl case. Where the end of the 38spl case ends on the base of your 9mm brass will tell you how long your bbl's chamber is.

It's getting more and more common for bbl's to be mfg'd with 1 little step in the process missing. The 1 minute it takes to use a throating reamer. A typical bbl as sent from the factory, note the sharp angle on the lands.

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The same bbl after a throating reamer was used on it.

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If your ammo is loaded long for a non-throated bbl, bad things can and will happen.

One of the most mis-understood pictures/instructions out there.

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Most people see that and see the simple word "accuracy" and the worm starts turning. You want to load your ammo just like the picture that says ok/normal.

Typical 1911 bbl's have chambers that are cut around 20/1000th's long than the saami brass length. I've owned several (18/19??) 1911's over the decades and it didn't matter if they were chambered in 45acp/38super/9mm. When the bbl's were correct, your reloads had around a thumbnail of bullet shoulder extending out of the case. A 45acp load that's been used for decades by countless 1000's of shooters, the h&g #68 with a .469/.470 crimp with a 1.250" oal. That load has the typical 20/1000th's shoulder hanging out of the case.

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I've seen people post that their 1911 won't pass the plunk test with a 1.250" oal and they're using 1.240" or other people have stated they use 1.265". That tells me their chambered off.

I have 3 different 9mm's right now. They are extremely different in design. A 1911 9mm/ a single action break bbl contender 9mm/plastic taurus pt111 g2 pocket 9mm. Built 20+ years apart, different mfg's and they all have the same chamber lengths. I use load all my 9mm ammo to the same oal for a specic bullet. What works in 1 firearm will chamber/work in the others.

2 of my favorite 9mm bullets, a 150gr hb fn bullet and a 125gr hp. They both have the same nose length/shoulder height making it easier to load them. Don't have to adjust the seating die when switching bullets.

When your bbl's are right and tight.

The contender @ 50yds doing a 10-shot group with that 150gr hb bullet.

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The taurus does as it should with that 125gr hp and full house loads of longshot. 1050fps and excellent expansion along with 3" 13-shot groups from the 3.2" bbl.

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Same 125gr hp, same oal this time being used in a nm 1911/9mm. A 10-shot group @50ft using a 1100fps target load.

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Any time I get a new/new to me firearm I always check the chamber and throat in the bbl's before I use them. Doesn't matter if it's .0002 minus pin gauges, shell casings, pound casts of rifle bbl's. No guessing, just results.

Short chambering is pretty common on  new barrels.
Especially ones marketed as 'gunsmith fit.'

It is one more place to adjust for tolerance stack across the parts assembled into an individual gun.

Typically gunsmith fit 1911 barrels (short chambers) and standard type1911 barrels (non ramped) will
have Issues that you have described...

Likely the best solution would be to rent go/no gauges and/or a chamber reamer to solve the Issues
you have described for having a safe gun...

Normally, the 9mm 1911's I have seen in the past function best with 10 lbs. to 14 lbs. recoil springs
depending your selected loads...with the lighter loads preferring lighter spring weights and visa versa.

Good luck.