Glock 19 Gen 4 vs Gen 5 barrel

For those interested...

Let's not confuse the facts with 'opinions'.

Many of the locking blocks of the Gen 5 pistols are the same as the Gen 4 pistols.

Please refer to Parts Order Form Certified Armorers Only 10218
https://us.glock.com/-/media/glock/...-form-certified-armorers-only-10218.pdf?la=en

As may be noted, in 9mm Luger, the Gen 5 standard frame locking block is the Gen 4 compact frame locking block. However, the Gen 3 to Gen 5 compact and subcompact locking blocks are the same.

'Blueprinting' a mechanical system (that is, manufacturing a product to the specified design dimensions with ZERO tolerances) does NOT make it less reliable.

In fact, it makes it MORE reliable.

To reduce cost, 'reasonable' tolerances are assigned to the dimensions of mechanical parts such that a majority of the finished products coming off the production line function as intended. However, given 'worst case tolerance stack ups', some of the products may experience 'issues' that need to be addressed. That's life in the 'mass-produced products' world.

As best as I can tell, the slide and outside barrel dimensions and tolerances didn't change. However, the GMB chamber and internal barrel tolerances seem to have been tightened a bit... in my opinion, to compete with the aftermarket 'match barrel' market.

Contrary to common 'misinformation', in compact and subcompact models, the Gen 5 barrels are indeed backward compatible.

Simply stated, the Gen 5 GMB barrel will fit and (properly) function in all pistols that share the same locking block as the Gen 5. For example, I've fit my G19 Gen 4 with a Gen 5 GMB barrel... and it functions perfectly (with NO 'tolerance' issues).

Also, note that Barsto and KKM started making 'world class' match barrels in 1977 and 'the early 1990's', respectively.

https://www.barsto.com/about.cfm
https://kkmprecision.com/about/

Battle Arms Development, Inc. (B.A.D. Inc.) is a design, research, and development firm incorporated in 2009. Note that they are NOT a manufacturer... my guess is that Battle Arms Development subcontract and purchase their products from third parties.

https://www.battlearmsdevelopment.com/about

In my opinion, the GMB barrel, ambidextrous slide stop lever (including the coil spring), the firing pin safety, and the trigger spring mechanism of the Gen 5 are significant improvements... all of which I've been (im)patiently waiting for... and Glock (finally) 'did it'.

Also, in my opinion, concerns relative to 'another entry for debris' are non-issues. Any additional areas of contamination ingress is minimal and marginal at worst and not cause for concern.

Am I an engineer?

Yes.

https://www.glockforum.com/threads/rsa-stock-stainless-or-tungsten.23706/page-2#post-1410505

Best regards,

Bob

Hi, Thoroughbreds!

Relative to tolerances in general, I think you're missing the point... there is an important difference between part 'tolerances' and part 'clearances'.

Read what I wrote...

"'Blueprinting' a mechanical system (that is, manufacturing a product to the specified design dimensions with ZERO tolerances) does NOT make it less reliable."

With precise cutting, a 'blueprinted' part has the optimal clearances for ALL of the design considerations... in this case... including dirt and crud. But, 'blueprinting' is very expensive.

At the other extreme, different parts, cut to the maximum allowable tolerances, may, in fact, reduce those clearances to zero... causing the parts to bind and the product to fail. "Loose' tolerances are good for making individual parts, but aren't necessarily good for the assembled product... IF the 'wrong' loose-tolerance parts are assembled together.

Specific to the barrel, the barrel hood, chamber, leade, groove diameter, and land diameter dimensions are the most critical... followed by the height of the rear lug (that typically 'floats just above' the locking block), the barrel outer diameter (that sits on the bottom of the slide cutout), and slide cutout inner diameter (which positions the muzzle of the barrel).

The clearances between the external dimensions of a barrel and the slide/frame are typically about 0.005" for 'drop-in' barrels and 0.002" for custom hand-fit barrels. However, even though these clearances seem very small, given the power and 'violence' of the slide cycle, dirt and crud in those areas are 'cleaned out' with every cycle.

The 'tighter' clearances between the slide/frame and the exterior of a 'match grade' barrel don't affect the 'whole firearm'... just the barrel fit.

A barrel that's 'too tight' (with a 'zero clearance' high spot somewhere) might 'stick' in the slide... and could be a problem... especially with a 'tired' or 'light spring weight' RSA.

But, such problems are rare and simply mean that the barrel fit should be 'adjusted' and/or the RSA should be replaced... easy 'fixes'.

The following videos may be of interest...

Hi, Thoroughbreds!

You're very welcome!

The only Gen 5 tolerance, clearance, fit, et cetera, differences I've noted are the chamber and leade of the Gen 5 GMB barrel.

All other Gen 5 tolerances, clearances, fits, et cetera, seem sufficiently similar to previous generations that they would be within the normal standard deviation of the product line as a whole.

To answer your question directly, a properly fit Barsto barrel should function just fine with no concern for failures related to tolerances and/or clearances.

Also, keep in mind that a single 'tolerance' in and of itself isn't what causes fit issues... it's the marriage of multiple 'worst case' tolerances that cause 'clearance' (fit) problems.

For example, simply stated, a 'big' (at max tolerance) part married with a 'small' (at min tolerance) part may function just fine, whereas a 'big' (at max tolerance) part married with another 'big' (at max tolerance) part may bind and not function properly.

(Why do you think Glock wants shooters to run a few hundred rounds through their 'problem pistol' before they send it in for warranty repair? It's to 'wear in' and eliminate these 'tight clearance' spots... if possible... so that the pistol 'fixes itself' and doesn't require repair.)

Hope this helps.

Best regards,

Bob

For those interested...

As previously mentioned, what I've noted is that the 'tighter tolerances' of the GMB barrel means that the chamber, leade, groove diameter, and land diameter are produced closer to the specified dimensions, with less 'drift' allowed toward the '+' tolerance, which results in 'tighter' barrels with increased consistency.

Please refer to the 9mm Luger SAAMI Standard in the picture below.

Note that the chamber, leade, groove diameter, and land diameter are specified dimensions with a '+' tolerance. In other words, SAAMI specifies a minimum chamber size and allows it to be bigger.

The cartridge is specified very slightly smaller with a '-' tolerance. In other words, SAAMI specifies a maximum cartridge size and allows it to be smaller.

For best consistency and accuracy, cartridges should be produced to 'just fit' the dimensions of the chamber and barrel. In other words, for best accuracy and consistency, the cartridges, chamber, leade, groove diameter, and land diameter should be manufactured to their specified dimensions with a '0' tolerance and the bullet should be seated 'just short' of the leade.

That would be an extremely tight fit... but it would be the most accurate and consistent.

Also, as I've mentioned, compared to their older siblings, I've not found much difference in the external dimensions of the GMB barrels... just typical normal standard deviation differences... which, in fact, could simply be measurement error on my part.

For what it's worth...

Best regards,

Bob

Are Glock 19 barrels interchangeable between generations?

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What kind of barrel does a Glock 19 Gen 5 have?