Compatibility, stated plainly
Which cartridges a firearm is chambered for, never signalled by colour alone — every match is written out.
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13,391
Firearms
142
Calibers
533
Manufacturers
Different eras. Different designs. Same passion for engineering and craftsmanship.
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By class of arm
Every entry is indexed to its chamberings — open a class to see what it covers.
How this works
Compatibility you can check, not guess
Chamberings are drawn from manufacturer specifications and cross-referenced across the catalogue.
Specifications you can trust
Bullet diameter, case length, pressure, velocity and energy — with the source of each figure recorded.
Read the methodologyCompare without a scorecard
Side-by-side comparison grouped by property, so the differences are what you read first.
Compare firearmsKnowledge builds confidence
History, chambering notes and technical reference — the context behind the numbers.
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Guides & comparisons
Long-form reference written to be read, cited and checked.
Featured comparison
Glock 19 vs SIG P320
Two dominant service pistols, compared on chambering, capacity, dimensions and the engineering choices behind each.
Read the comparisonAlso on MatchMyGun