LIbrary of Congress is archival information.
Current versions of the US Code are located here:
Pertinent info re: SS 4307 - 8:
[§§4307, 4308. Repealed. Pub. L. 104–106, div. A, title XVI, §1624(a)(1), Feb. 10, 1996, 110 Stat. 522]
Section 4307, act Aug. 10, 1956, ch. 1041, 70A Stat. 235, permitted President to detail commissioned officer of the Army or of the Marine Corps as director of civilian marksmanship.
Section 4308, acts Aug. 10, 1956, ch. 1041, 70A Stat. 236; Nov. 14, 1986, Pub. L. 99–661, div. A, title III, §318(a), 100 Stat. 3855; Nov. 5, 1990, Pub. L. 101–510, div. A, title III, §328(b)–(d), (g)(1), 104 Stat. 1533, 1534; Oct. 23, 1992, Pub. L. 102–484, div. A, title III, §380(a)(1), 106 Stat. 2389; Nov. 30, 1993, Pub. L. 103–160, div. A, title III, §372, 107 Stat. 1635, related to authority of Secretary of the Army to promote civilian marksmanship. See section 40701 et seq. of Title 36, Patriotic and National Observances, Ceremonies, and Organizations.
Effective Date of Repeal
Repeal effective on the earlier of the date on which the Secretary of the Army submits a certification in accordance with section 5523 of [former] Title 36, Patriotic Societies and Observances, or Oct. 1, 1996, see section 1624(c) of Pub. L. 104–106, set out as an Effective Date of 1996 Amendment note under section 925 of Title 18, Crimes and Criminal Procedure.
—— Note in the current version, SS4309 states:
§4309. Rifle ranges: availability for use by members and civilians
(a) Ranges Available.—All rifle ranges constructed in whole or in part with funds provided by the United States may be used by members of the armed forces and by persons capable of bearing arms.
The operative word in part a is may. In context, it means that It’s optional for DoD to do this.
Part 3 of SS4309 goes on to state:
(3) Use of a rifle range referred to in paragraph (1) by civilians may not interfere with the use of the range by members of the armed forces.
In the context of SS4309, may is imperative in that it is mandatory that civilians not interfere with with usage of the range by members of the military. That gives broad latitude to the services, and ultimately to each installation to develop regulations in order to comply both with the law and prove that in doing so, they are not allowing civilian use to impede access to military members.
Creatively, Ft Carson solves this problem by using non-appropriated and partner funds to circumvent the entirety of the section. Non-appropriated funds and partner funds are not provide by the United States, they are provided by other entities and/or revenue sources.